---
title: "Tutorial: Membangun agen yang menggunakan alat"
url: https://platform.claude.com/docs/id/agents-and-tools/tool-use/build-a-tool-using-agent
description: Panduan langkah demi langkah dari satu panggilan alat hingga loop agentik yang siap produksi.
---
Tutorial ini membangun agen pengelola kalender dalam lima cincin konsentris. Setiap cincin adalah program lengkap yang dapat dijalankan dan menambahkan tepat satu konsep ke cincin sebelumnya. Pada akhirnya, Anda akan telah menulis "agentic loop" (loop agentik) secara manual lalu menggantinya dengan abstraksi SDK Tool Runner.
Alat contohnya adalah `create_calendar_event`. Skemanya menggunakan objek bersarang, array, dan field opsional, sehingga Anda akan melihat bagaimana Claude menangani bentuk input yang realistis, bukan hanya satu string datar.
Setiap cincin berjalan secara mandiri. Salin cincin mana pun ke file baru dan cincin tersebut akan berjalan tanpa kode dari cincin-cincin sebelumnya.
## Cincin 1: Satu alat, satu giliran
Program pengguna alat terkecil yang mungkin: satu alat, satu pesan pengguna, satu panggilan alat, satu hasil. Kodenya diberi banyak komentar sehingga Anda dapat memetakan setiap baris ke [siklus hidup penggunaan alat](https://platform.claude.com/docs/id/agents-and-tools/tool-use/how-tool-use-works).
Permintaan mengirimkan array `tools` bersama pesan pengguna. Ketika Claude menentukan bahwa panggilan alat diperlukan, respons kembali dengan `stop_reason: "tool_use"` dan blok konten `tool_use` yang berisi nama alat, `id` unik, dan `input` terstruktur. Kode Anda menjalankan alat tersebut, lalu mengirimkan hasilnya kembali dalam blok `tool_result` yang `tool_use_id`-nya cocok dengan `id` dari panggilan tersebut.
```bash cURL
#!/bin/bash
# Ring 1: Single tool, single turn.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```bash CLI
#!/usr/bin/env bash
# Ring 1: Single tool, single turn.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```python Python
# Ring 1: Satu alat, satu giliran.
import json
import anthropic
# Buat klien. Klien membaca ANTHROPIC_API_KEY dari environment.
client = anthropic.Anthropic()
# Definisikan satu alat. input_schema adalah objek JSON Schema yang mendeskripsikan
# argumen yang harus diteruskan Claude saat memanggil alat ini. Skema ini
# mencakup objek bersarang (recurrence), array (attendees), dan field
# opsional, yang lebih mendekati alat dunia nyata daripada argumen string datar.
tools = [
{
"name": "create_calendar_event",
"description": "Create a calendar event with attendees and optional recurrence.",
"input_schema": {
"type": "object",
"properties": {
"title": {"type": "string"},
"start": {"type": "string", "format": "date-time"},
"end": {"type": "string", "format": "date-time"},
"attendees": {
"type": "array",
"items": {"type": "string", "format": "email"},
},
"recurrence": {
"type": "object",
"properties": {
"frequency": {"enum": ["daily", "weekly", "monthly"]},
"count": {"type": "integer", "minimum": 1},
},
},
},
"required": ["title", "start", "end"],
},
}
]
# Kirim permintaan pengguna bersama definisi alat. Claude memutuskan
# apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat.
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
tool_choice={"type": "auto", "disable_parallel_tool_use": True},
messages=[
{
"role": "user",
"content": "Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am.",
}
],
)
# Ketika Claude memanggil alat, respons memiliki stop_reason "tool_use"
# dan array content berisi blok tool_use di samping teks apa pun.
print(f"stop_reason: {response.stop_reason}")
# Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
# tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
tool_use = next(block for block in response.content if block.type == "tool_use")
print(f"Tool: {tool_use.name}")
print(f"Input: {tool_use.input}")
# Eksekusi alat. Di sistem nyata, ini akan memanggil API kalender Anda.
# Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
result = {"event_id": "evt_123", "status": "created"}
# Kirim hasilnya kembali. Blok tool_result masuk ke pesan user dan
# tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
# asisten sebelumnya disertakan agar Claude memiliki riwayat lengkap.
followup = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
tool_choice={"type": "auto", "disable_parallel_tool_use": True},
messages=[
{
"role": "user",
"content": "Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am.",
},
{"role": "assistant", "content": response.content},
{
"role": "user",
"content": [
{
"type": "tool_result",
"tool_use_id": tool_use.id,
"content": json.dumps(result),
}
],
},
],
)
# Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam
# bahasa alami dan stop_reason menjadi "end_turn".
print(f"stop_reason: {followup.stop_reason}")
final_text = next(block for block in followup.content if block.type == "text")
print(final_text.text)
```
```typescript TypeScript
// Ring 1: Satu alat, satu giliran.
import Anthropic from "@anthropic-ai/sdk";
// Buat klien. Klien membaca ANTHROPIC_API_KEY dari environment.
const client = new Anthropic();
// Definisikan satu alat. input_schema adalah objek JSON Schema yang mendeskripsikan
// argumen yang harus diteruskan Claude saat memanggil alat ini. Skema ini
// mencakup objek bersarang (recurrence), array (attendees), dan field
// opsional, yang lebih mendekati alat dunia nyata daripada argumen string datar.
const tools: Anthropic.Tool[] = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: { type: "string" },
start: { type: "string", format: "date-time" },
end: { type: "string", format: "date-time" },
attendees: {
type: "array",
items: { type: "string", format: "email" }
},
recurrence: {
type: "object",
properties: {
frequency: { enum: ["daily", "weekly", "monthly"] },
count: { type: "integer", minimum: 1 }
}
}
},
required: ["title", "start", "end"]
}
}
];
// Kirim permintaan pengguna bersama definisi alat. Claude memutuskan
// apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat.
const response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
tool_choice: { type: "auto", disable_parallel_tool_use: true },
messages: [
{
role: "user",
content:
"Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am."
}
]
});
// Ketika Claude memanggil alat, respons memiliki stop_reason "tool_use"
// dan array content berisi blok tool_use di samping teks apa pun.
console.log(`stop_reason: ${response.stop_reason}`);
// Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
// tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
const toolUse = response.content.find((block) => block.type === "tool_use")!;
console.log(`Tool: ${toolUse.name}`);
console.log(`Input: ${JSON.stringify(toolUse.input)}`);
// Eksekusi alat. Di sistem nyata, ini akan memanggil API kalender Anda.
// Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
const result = { event_id: "evt_123", status: "created" };
// Kirim hasilnya kembali. Blok tool_result masuk ke pesan user dan
// tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
// assistant sebelumnya disertakan agar Claude memiliki riwayat lengkap.
const followup = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
tool_choice: { type: "auto", disable_parallel_tool_use: true },
messages: [
{
role: "user",
content:
"Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am."
},
{ role: "assistant", content: response.content },
{
role: "user",
content: [
{
type: "tool_result",
tool_use_id: toolUse.id,
content: JSON.stringify(result)
}
]
}
]
});
// Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam
// bahasa alami dan stop_reason menjadi "end_turn".
console.log(`stop_reason: ${followup.stop_reason}`);
for (const block of followup.content) {
if (block.type === "text") {
console.log(block.text);
}
}
```
```csharp C#
// Ring 1: Satu alat, satu giliran.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Threading.Tasks;
using Anthropic;
using Anthropic.Models.Messages;
// Buat klien. Klien membaca ANTHROPIC_API_KEY dari environment.
AnthropicClient client = new();
// Definisikan satu alat. Skema input adalah objek JSON Schema yang mendeskripsikan
// argumen yang harus diteruskan Claude saat memanggil alat ini. Skema ini
// mencakup objek bersarang (recurrence), array (attendees), dan field
// opsional, yang lebih mendekati alat dunia nyata daripada argumen string datar.
List tools =
[
new ToolUnion(new Tool()
{
Name = "create_calendar_event",
Description = "Create a calendar event with attendees and optional recurrence.",
InputSchema = new InputSchema()
{
Properties = new Dictionary
{
["title"] = JsonSerializer.SerializeToElement(new { type = "string" }),
["start"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["end"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["attendees"] = JsonSerializer.SerializeToElement(new
{
type = "array",
items = new { type = "string", format = "email" },
}),
["recurrence"] = JsonSerializer.SerializeToElement(new
{
type = "object",
properties = new
{
frequency = new { @enum = new[] { "daily", "weekly", "monthly" } },
count = new { type = "integer", minimum = 1 },
},
}),
},
Required = ["title", "start", "end"],
},
}),
];
// Minta paling banyak satu pemanggilan alat per giliran agar alur satu giliran di bawah
// tetap dapat diprediksi.
var toolChoice = new ToolChoice(new ToolChoiceAuto { DisableParallelToolUse = true });
const string userPrompt =
"Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am.";
// Kirim permintaan pengguna bersama definisi alat. Claude memutuskan
// apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat tersebut.
var response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
ToolChoice = toolChoice,
Messages = [new() { Role = Role.User, Content = userPrompt }],
});
// Saat Claude memanggil alat, respons memiliki stop_reason "tool_use"
// dan array content berisi blok tool_use di samping teks apa pun.
Console.WriteLine($"stop_reason: {response.StopReason?.Raw()}");
// Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
// tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
ToolUseBlock? toolUse = null;
foreach (var block in response.Content)
{
if (block.TryPickToolUse(out var picked))
{
toolUse = picked;
break;
}
}
Console.WriteLine($"Tool: {toolUse!.Name}");
Console.WriteLine($"Input: {JsonSerializer.Serialize(toolUse.Input)}");
// Jalankan alat. Di sistem nyata, ini akan memanggil API kalender Anda.
// Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
var result = """{"event_id": "evt_123", "status": "created"}""";
// Kirim hasilnya kembali. Blok tool_result ditempatkan dalam pesan user dan
// tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
// assistant sebelumnya disertakan agar Claude memiliki riwayat lengkap.
List toolResults =
[
new ContentBlockParam(new ToolResultBlockParam()
{
ToolUseID = toolUse.ID,
Content = result,
}),
];
var followup = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
ToolChoice = toolChoice,
Messages =
[
new() { Role = Role.User, Content = userPrompt },
new() { Role = Role.Assistant, Content = response.Content.Select(block => new ContentBlockParam(block.Json)).ToList() },
new() { Role = Role.User, Content = new MessageParamContent(toolResults) },
],
});
// Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam bahasa
// alami dan stop_reason menjadi "end_turn".
Console.WriteLine($"stop_reason: {followup.StopReason?.Raw()}");
foreach (var block in followup.Content)
{
if (block.TryPickText(out var text))
{
Console.WriteLine(text.Text);
}
}
```
```go Go
// Ring 1: Satu alat, satu giliran.
package main
import (
"context"
"fmt"
"log"
"github.com/anthropics/anthropic-sdk-go"
)
func main() {
// Buat klien. Klien ini membaca ANTHROPIC_API_KEY dari environment.
client := anthropic.NewClient()
ctx := context.Background()
// Definisikan satu alat. Skema input adalah objek JSON Schema yang mendeskripsikan
// argumen yang harus diteruskan Claude saat memanggil alat ini. Skema ini
// mencakup objek bersarang (recurrence), array (attendees), dan field
// opsional, yang lebih mendekati alat dunia nyata daripada argumen string datar.
tools := []anthropic.ToolUnionParam{
{OfTool: &anthropic.ToolParam{
Name: "create_calendar_event",
Description: anthropic.String("Create a calendar event with attendees and optional recurrence."),
InputSchema: anthropic.ToolInputSchemaParam{
Properties: map[string]any{
"title": map[string]any{"type": "string"},
"start": map[string]any{"type": "string", "format": "date-time"},
"end": map[string]any{"type": "string", "format": "date-time"},
"attendees": map[string]any{
"type": "array",
"items": map[string]any{"type": "string", "format": "email"},
},
"recurrence": map[string]any{
"type": "object",
"properties": map[string]any{
"frequency": map[string]any{"enum": []string{"daily", "weekly", "monthly"}},
"count": map[string]any{"type": "integer", "minimum": 1},
},
},
},
Required: []string{"title", "start", "end"},
},
}},
}
// Minta paling banyak satu pemanggilan alat per giliran agar alur satu giliran di bawah
// tetap dapat diprediksi.
toolChoice := anthropic.ToolChoiceUnionParam{
OfAuto: &anthropic.ToolChoiceAutoParam{DisableParallelToolUse: anthropic.Bool(true)},
}
userMessage := anthropic.NewUserMessage(anthropic.NewTextBlock(
"Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am.",
))
// Kirim permintaan pengguna bersama dengan definisi alat. Claude memutuskan
// apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat tersebut.
response, err := client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
ToolChoice: toolChoice,
Messages: []anthropic.MessageParam{userMessage},
})
if err != nil {
log.Fatal(err)
}
// Ketika Claude memanggil alat, respons memiliki stop_reason "tool_use"
// dan array content berisi blok tool_use di samping teks apa pun.
fmt.Printf("stop_reason: %s\n", response.StopReason)
// Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
// tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
var toolUse anthropic.ContentBlockUnion
for _, block := range response.Content {
if block.Type == "tool_use" {
toolUse = block
break
}
}
fmt.Printf("Tool: %s\n", toolUse.Name)
fmt.Printf("Input: %s\n", string(toolUse.Input))
// Jalankan alat. Dalam sistem nyata, ini akan memanggil API kalender Anda.
// Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
result := `{"event_id": "evt_123", "status": "created"}`
// Kirim hasilnya kembali. Blok tool_result ditempatkan dalam pesan user dan
// tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
// asisten sebelumnya disertakan agar Claude memiliki riwayat lengkap.
var assistantContent []anthropic.ContentBlockParamUnion
for _, block := range response.Content {
assistantContent = append(assistantContent, block.ToParam())
}
followup, err := client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
ToolChoice: toolChoice,
Messages: []anthropic.MessageParam{
userMessage,
anthropic.NewAssistantMessage(assistantContent...),
anthropic.NewUserMessage(anthropic.NewToolResultBlock(toolUse.ID, result, false)),
},
})
if err != nil {
log.Fatal(err)
}
// Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam bahasa
// alami dan stop_reason menjadi "end_turn".
fmt.Printf("stop_reason: %s\n", followup.StopReason)
for _, block := range followup.Content {
if block.Type == "text" {
fmt.Println(block.Text)
}
}
}
```
```java Java
// Ring 1: Satu alat, satu giliran.
import com.anthropic.client.AnthropicClient;
import com.anthropic.client.okhttp.AnthropicOkHttpClient;
import com.anthropic.core.JsonValue;
import com.anthropic.models.messages.ContentBlockParam;
import com.anthropic.models.messages.Message;
import com.anthropic.models.messages.MessageCreateParams;
import com.anthropic.models.messages.Model;
import com.anthropic.models.messages.Tool;
import com.anthropic.models.messages.Tool.InputSchema;
import com.anthropic.models.messages.ToolChoiceAuto;
import com.anthropic.models.messages.ToolResultBlockParam;
import com.anthropic.models.messages.ToolUseBlock;
import java.util.List;
import java.util.Map;
void main() {
// Buat klien. Klien membaca ANTHROPIC_API_KEY dari environment.
AnthropicClient client = AnthropicOkHttpClient.fromEnv();
// Definisikan satu alat. Skema input adalah objek JSON Schema yang mendeskripsikan
// argumen yang harus diteruskan Claude saat memanggil alat ini. Skema ini
// mencakup objek bersarang (recurrence), array (attendees), dan field
// opsional, yang lebih mendekati alat dunia nyata daripada argumen string datar.
Tool calendarTool = Tool.builder()
.name("create_calendar_event")
.description("Create a calendar event with attendees and optional recurrence.")
.inputSchema(InputSchema.builder()
.properties(JsonValue.from(Map.of(
"title", Map.of("type", "string"),
"start", Map.of("type", "string", "format", "date-time"),
"end", Map.of("type", "string", "format", "date-time"),
"attendees", Map.of(
"type", "array",
"items", Map.of("type", "string", "format", "email")
),
"recurrence", Map.of(
"type", "object",
"properties", Map.of(
"frequency", Map.of("enum", List.of("daily", "weekly", "monthly")),
"count", Map.of("type", "integer", "minimum", 1)
)
)
)))
.required(List.of("title", "start", "end"))
.build())
.build();
// Minta paling banyak satu pemanggilan alat per giliran agar alur satu giliran di bawah
// tetap dapat diprediksi.
ToolChoiceAuto toolChoice = ToolChoiceAuto.builder()
.disableParallelToolUse(true)
.build();
String userPrompt =
"Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am.";
// Kirim permintaan pengguna bersama definisi alat. Claude memutuskan
// apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat tersebut.
Message response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.toolChoice(toolChoice)
.addUserMessage(userPrompt)
.build());
// Ketika Claude memanggil alat, respons memiliki stop_reason "tool_use"
// dan array content berisi blok tool_use di samping teks apa pun.
IO.println("stop_reason: " + response.stopReason().orElse(null));
// Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
// tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
ToolUseBlock toolUse = response.content().stream()
.flatMap(block -> block.toolUse().stream())
.findFirst()
.orElseThrow();
IO.println("Tool: " + toolUse.name());
IO.println("Input: " + toolUse._input());
// Jalankan alat. Dalam sistem nyata, ini akan memanggil API kalender Anda.
// Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
String result = "{\"event_id\": \"evt_123\", \"status\": \"created\"}";
// Kirim hasilnya kembali. Blok tool_result ditempatkan dalam pesan user dan
// tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
// asisten sebelumnya disertakan agar Claude memiliki riwayat lengkap.
Message followup = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.toolChoice(toolChoice)
.addUserMessage(userPrompt)
.addMessage(response)
.addUserMessageOfBlockParams(List.of(ContentBlockParam.ofToolResult(
ToolResultBlockParam.builder()
.toolUseId(toolUse.id())
.content(result)
.build())))
.build());
// Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam bahasa
// alami dan stop_reason menjadi "end_turn".
IO.println("stop_reason: " + followup.stopReason().orElse(null));
followup.content().stream()
.flatMap(block -> block.text().stream())
.forEach(textBlock -> IO.println(textBlock.text()));
}
```
```php PHP
'create_calendar_event',
'description' => 'Create a calendar event with attendees and optional recurrence.',
'input_schema' => [
'type' => 'object',
'properties' => [
'title' => ['type' => 'string'],
'start' => ['type' => 'string', 'format' => 'date-time'],
'end' => ['type' => 'string', 'format' => 'date-time'],
'attendees' => [
'type' => 'array',
'items' => ['type' => 'string', 'format' => 'email'],
],
'recurrence' => [
'type' => 'object',
'properties' => [
'frequency' => ['enum' => ['daily', 'weekly', 'monthly']],
'count' => ['type' => 'integer', 'minimum' => 1],
],
],
],
'required' => ['title', 'start', 'end'],
],
],
];
$userMessage = [
'role' => 'user',
'content' => 'Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am.',
];
// Minta paling banyak satu pemanggilan alat per giliran agar alur satu giliran di bawah
// tetap dapat diprediksi.
$toolChoice = ToolChoiceAuto::with(disableParallelToolUse: true);
// Kirim permintaan pengguna bersama definisi alat. Claude memutuskan
// apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat tersebut.
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
toolChoice: $toolChoice,
messages: [$userMessage],
);
// Ketika Claude memanggil alat, respons memiliki stop_reason "tool_use"
// dan array content berisi blok tool_use di samping teks apa pun.
printf("stop_reason: %s\n", $response->stopReason);
// Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
// tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
$toolUse = null;
foreach ($response->content as $block) {
if ($block->type === 'tool_use') {
$toolUse = $block;
break;
}
}
printf("Tool: %s\n", $toolUse->name);
printf("Input: %s\n", json_encode($toolUse->input));
// Jalankan alat. Dalam sistem nyata, ini akan memanggil API kalender Anda.
// Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
$result = ['event_id' => 'evt_123', 'status' => 'created'];
// Kirim hasilnya kembali. Blok tool_result ditempatkan dalam pesan user dan
// tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
// assistant sebelumnya disertakan agar Claude memiliki riwayat lengkap.
$followup = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
toolChoice: $toolChoice,
messages: [
$userMessage,
['role' => 'assistant', 'content' => $response->content],
[
'role' => 'user',
'content' => [
[
'type' => 'tool_result',
'tool_use_id' => $toolUse->id,
'content' => json_encode($result),
],
],
],
],
);
// Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam bahasa
// alami dan stop_reason menjadi "end_turn".
printf("stop_reason: %s\n", $followup->stopReason);
foreach ($followup->content as $block) {
if ($block->type === 'text') {
echo $block->text, "\n";
}
}
```
```ruby Ruby
# Ring 1: Satu alat, satu giliran.
require "anthropic"
# Buat klien. Klien ini membaca ANTHROPIC_API_KEY dari environment.
client = Anthropic::Client.new
# Definisikan satu alat. input_schema adalah objek JSON Schema yang mendeskripsikan
# argumen yang harus diteruskan Claude saat memanggil alat ini. Skema ini
# mencakup objek bersarang (recurrence), array (attendees), dan field
# opsional, yang lebih mendekati alat dunia nyata daripada argumen string datar.
tools = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: {type: "string"},
start: {type: "string", format: "date-time"},
end: {type: "string", format: "date-time"},
attendees: {
type: "array",
items: {type: "string", format: "email"}
},
recurrence: {
type: "object",
properties: {
frequency: {enum: ["daily", "weekly", "monthly"]},
count: {type: "integer", minimum: 1}
}
}
},
required: ["title", "start", "end"]
}
}
]
user_message = {
role: "user",
content: "Schedule a 30-minute sync with alice@example.com and bob@example.com on Monday, March 30, 2026 at 10am."
}
# Minta paling banyak satu pemanggilan alat per giliran agar alur satu giliran di bawah
# tetap dapat diprediksi.
tool_choice = {type: "auto", disable_parallel_tool_use: true}
# Kirim permintaan pengguna bersama definisi alat. Claude memutuskan
# apakah akan memanggil alat berdasarkan permintaan dan deskripsi alat tersebut.
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
tool_choice: tool_choice,
messages: [user_message]
)
# Ketika Claude memanggil alat, respons memiliki stop_reason "tool_use"
# dan array content berisi blok tool_use di samping teks apa pun.
puts "stop_reason: #{response.stop_reason}"
# Temukan blok tool_use. Respons mungkin berisi blok teks sebelum blok
# tool_use, jadi pindai array content alih-alih mengasumsikan posisinya.
tool_use = response.content.find { |block| block.type == :tool_use }
puts "Tool: #{tool_use.name}"
puts "Input: #{tool_use.input}"
# Eksekusi alat. Di sistem nyata, ini akan memanggil API kalender Anda.
# Di sini hasilnya di-hardcode agar contoh ini tetap mandiri.
result = {event_id: "evt_123", status: "created"}
# Kirim hasilnya kembali. Blok tool_result ditempatkan dalam pesan user dan
# tool_use_id-nya harus cocok dengan id dari blok tool_use di atas. Respons
# assistant sebelumnya disertakan agar Claude memiliki riwayat lengkap.
followup = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
tool_choice: tool_choice,
messages: [
user_message,
{role: "assistant", content: response.content},
{
role: "user",
content: [
{
type: "tool_result",
tool_use_id: tool_use.id,
content: JSON.generate(result)
}
]
}
]
)
# Dengan hasil alat di tangan, Claude menghasilkan jawaban akhir dalam bahasa
# alami dan stop_reason menjadi "end_turn".
puts "stop_reason: #{followup.stop_reason}"
followup.content.each do |block|
puts block.text if block.type == :text
end
```
**Apa yang diharapkan**
```text Output wrap
stop_reason: tool_use
Tool: create_calendar_event
Input: {'title': 'Sync', 'start': '2026-03-30T10:00:00', 'end': '2026-03-30T10:30:00', 'attendees': ['alice@example.com', 'bob@example.com']}
stop_reason: end_turn
I've scheduled your 30-minute sync with Alice and Bob for Monday, March 30 at 10am.
```
`stop_reason` pertama adalah `tool_use` karena Claude sedang menunggu hasil kalender. Setelah Anda mengirimkan hasilnya, `stop_reason` kedua adalah `end_turn` dan kontennya berupa bahasa alami untuk pengguna.
## Cincin 2: Loop agentik
Cincin 1 mengasumsikan Claude akan memanggil alat tepat satu kali. Tugas nyata sering membutuhkan beberapa panggilan: Claude mungkin membuat sebuah acara, membaca konfirmasinya, lalu membuat acara lain. Solusinya adalah loop `while` yang terus menjalankan alat dan mengirimkan hasilnya kembali hingga `stop_reason` tidak lagi `"tool_use"`.
Perubahan lainnya adalah riwayat percakapan. Alih-alih membangun ulang array `messages` dari awal pada setiap permintaan, simpan daftar berjalan dan tambahkan ke dalamnya. Setiap giliran melihat konteks sebelumnya secara lengkap.
```bash cURL
#!/bin/bash
# Ring 2: The agentic loop.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```bash CLI
#!/usr/bin/env bash
# Ring 2: The agentic loop.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```python Python
# Ring 2: Loop agentik.
import json
import anthropic
client = anthropic.Anthropic()
tools = [
{
"name": "create_calendar_event",
"description": "Create a calendar event with attendees and optional recurrence.",
"input_schema": {
"type": "object",
"properties": {
"title": {"type": "string"},
"start": {"type": "string", "format": "date-time"},
"end": {"type": "string", "format": "date-time"},
"attendees": {
"type": "array",
"items": {"type": "string", "format": "email"},
},
"recurrence": {
"type": "object",
"properties": {
"frequency": {"enum": ["daily", "weekly", "monthly"]},
"count": {"type": "integer", "minimum": 1},
},
},
},
"required": ["title", "start", "end"],
},
}
]
def run_tool(name, tool_input):
if name == "create_calendar_event":
return {
"event_id": "evt_123",
"status": "created",
"title": tool_input["title"],
}
return {"error": f"Unknown tool: {name}"}
# Simpan seluruh riwayat percakapan dalam list agar setiap giliran melihat konteks sebelumnya.
messages = [
{
"role": "user",
"content": "Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com.",
}
]
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
tool_choice={"type": "auto", "disable_parallel_tool_use": True},
messages=messages,
)
# Ulangi hingga Claude berhenti meminta alat. Setiap iterasi menjalankan alat yang diminta,
# menambahkan hasilnya ke riwayat, lalu meminta Claude untuk melanjutkan.
while response.stop_reason == "tool_use":
tool_use = next(block for block in response.content if block.type == "tool_use")
result = run_tool(tool_use.name, tool_use.input)
messages.append({"role": "assistant", "content": response.content})
messages.append(
{
"role": "user",
"content": [
{
"type": "tool_result",
"tool_use_id": tool_use.id,
"content": json.dumps(result),
}
],
}
)
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
tool_choice={"type": "auto", "disable_parallel_tool_use": True},
messages=messages,
)
final_text = next(block for block in response.content if block.type == "text")
print(final_text.text)
```
```typescript TypeScript
// Ring 2: Loop agentik.
import Anthropic from "@anthropic-ai/sdk";
const client = new Anthropic();
const tools: Anthropic.Tool[] = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: { type: "string" },
start: { type: "string", format: "date-time" },
end: { type: "string", format: "date-time" },
attendees: {
type: "array",
items: { type: "string", format: "email" }
},
recurrence: {
type: "object",
properties: {
frequency: { enum: ["daily", "weekly", "monthly"] },
count: { type: "integer", minimum: 1 }
}
}
},
required: ["title", "start", "end"]
}
}
];
function runTool(name: string, input: Record) {
if (name === "create_calendar_event") {
return { event_id: "evt_123", status: "created", title: input.title };
}
return { error: `Unknown tool: ${name}` };
}
// Simpan seluruh riwayat percakapan agar setiap giliran melihat konteks sebelumnya.
const messages: Anthropic.MessageParam[] = [
{
role: "user",
content:
"Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com."
}
];
let response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
tool_choice: { type: "auto", disable_parallel_tool_use: true },
messages
});
// Ulangi hingga Claude berhenti meminta alat. Setiap iterasi menjalankan alat
// yang diminta, menambahkan hasilnya ke riwayat, lalu meminta Claude melanjutkan.
while (response.stop_reason === "tool_use") {
const toolUse = response.content.find((block) => block.type === "tool_use")!;
const result = runTool(toolUse.name, toolUse.input as Record);
messages.push({ role: "assistant", content: response.content });
messages.push({
role: "user",
content: [
{
type: "tool_result",
tool_use_id: toolUse.id,
content: JSON.stringify(result)
}
]
});
response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
tool_choice: { type: "auto", disable_parallel_tool_use: true },
messages
});
}
for (const block of response.content) {
if (block.type === "text") {
console.log(block.text);
}
}
```
```csharp C#
// Ring 2: Loop agentik.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Threading.Tasks;
using Anthropic;
using Anthropic.Models.Messages;
AnthropicClient client = new();
List tools =
[
new ToolUnion(new Tool()
{
Name = "create_calendar_event",
Description = "Create a calendar event with attendees and optional recurrence.",
InputSchema = new InputSchema()
{
Properties = new Dictionary
{
["title"] = JsonSerializer.SerializeToElement(new { type = "string" }),
["start"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["end"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["attendees"] = JsonSerializer.SerializeToElement(new
{
type = "array",
items = new { type = "string", format = "email" },
}),
["recurrence"] = JsonSerializer.SerializeToElement(new
{
type = "object",
properties = new
{
frequency = new { @enum = new[] { "daily", "weekly", "monthly" } },
count = new { type = "integer", minimum = 1 },
},
}),
},
Required = ["title", "start", "end"],
},
}),
];
// Jalankan alat yang diminta dan kembalikan hasilnya sebagai string.
string RunTool(ToolUseBlock toolUse)
{
if (toolUse.Name == "create_calendar_event")
{
var title = toolUse.Input.TryGetValue("title", out var t) ? t.GetString() : "";
return JsonSerializer.Serialize(new { event_id = "evt_123", status = "created", title });
}
return JsonSerializer.Serialize(new { error = $"Unknown tool: {toolUse.Name}" });
}
var toolChoice = new ToolChoice(new ToolChoiceAuto { DisableParallelToolUse = true });
// Simpan seluruh riwayat percakapan dalam list agar setiap giliran melihat konteks sebelumnya.
List messages =
[
new()
{
Role = Role.User,
Content = "Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com.",
},
];
var response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
ToolChoice = toolChoice,
Messages = messages,
});
// Ulangi hingga Claude berhenti meminta alat. Setiap iterasi menjalankan alat
// yang diminta, menambahkan hasilnya ke riwayat, lalu meminta Claude melanjutkan.
while (response.StopReason == StopReason.ToolUse)
{
ToolUseBlock? toolUse = null;
foreach (var block in response.Content)
{
if (block.TryPickToolUse(out var picked))
{
toolUse = picked;
break;
}
}
var result = RunTool(toolUse!);
messages.Add(new()
{
Role = Role.Assistant,
Content = response.Content.Select(block => new ContentBlockParam(block.Json)).ToList(),
});
messages.Add(new()
{
Role = Role.User,
Content = new MessageParamContent(
[
new ContentBlockParam(new ToolResultBlockParam() { ToolUseID = toolUse!.ID, Content = result }),
]),
});
response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
ToolChoice = toolChoice,
Messages = messages,
});
}
foreach (var block in response.Content)
{
if (block.TryPickText(out var text))
{
Console.WriteLine(text.Text);
}
}
```
```go Go
// Ring 2: Loop agentik.
package main
import (
"context"
"encoding/json"
"fmt"
"log"
"github.com/anthropics/anthropic-sdk-go"
)
func runTool(name string, input map[string]any) string {
if name == "create_calendar_event" {
title, _ := input["title"].(string)
return fmt.Sprintf(`{"event_id": "evt_123", "status": "created", "title": %q}`, title)
}
return fmt.Sprintf(`{"error": "Unknown tool: %s"}`, name)
}
func main() {
client := anthropic.NewClient()
ctx := context.Background()
tools := []anthropic.ToolUnionParam{
{OfTool: &anthropic.ToolParam{
Name: "create_calendar_event",
Description: anthropic.String("Create a calendar event with attendees and optional recurrence."),
InputSchema: anthropic.ToolInputSchemaParam{
Properties: map[string]any{
"title": map[string]any{"type": "string"},
"start": map[string]any{"type": "string", "format": "date-time"},
"end": map[string]any{"type": "string", "format": "date-time"},
"attendees": map[string]any{
"type": "array",
"items": map[string]any{"type": "string", "format": "email"},
},
"recurrence": map[string]any{
"type": "object",
"properties": map[string]any{
"frequency": map[string]any{"enum": []string{"daily", "weekly", "monthly"}},
"count": map[string]any{"type": "integer", "minimum": 1},
},
},
},
Required: []string{"title", "start", "end"},
},
}},
}
toolChoice := anthropic.ToolChoiceUnionParam{
OfAuto: &anthropic.ToolChoiceAutoParam{DisableParallelToolUse: anthropic.Bool(true)},
}
// Simpan seluruh riwayat percakapan dalam slice agar setiap giliran melihat konteks sebelumnya.
messages := []anthropic.MessageParam{
anthropic.NewUserMessage(anthropic.NewTextBlock(
"Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com.",
)),
}
response, err := client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
ToolChoice: toolChoice,
Messages: messages,
})
if err != nil {
log.Fatal(err)
}
// Ulangi hingga Claude berhenti meminta alat. Setiap iterasi menjalankan alat yang diminta,
// menambahkan hasilnya ke riwayat, lalu meminta Claude untuk melanjutkan.
for response.StopReason == "tool_use" {
var toolUse anthropic.ContentBlockUnion
for _, block := range response.Content {
if block.Type == "tool_use" {
toolUse = block
break
}
}
var input map[string]any
if err := json.Unmarshal(toolUse.Input, &input); err != nil {
log.Fatal(err)
}
result := runTool(toolUse.Name, input)
var assistantContent []anthropic.ContentBlockParamUnion
for _, block := range response.Content {
assistantContent = append(assistantContent, block.ToParam())
}
messages = append(messages, anthropic.NewAssistantMessage(assistantContent...))
messages = append(messages, anthropic.NewUserMessage(
anthropic.NewToolResultBlock(toolUse.ID, result, false),
))
response, err = client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
ToolChoice: toolChoice,
Messages: messages,
})
if err != nil {
log.Fatal(err)
}
}
for _, block := range response.Content {
if block.Type == "text" {
fmt.Println(block.Text)
}
}
}
```
```java Java
// Ring 2: Loop agentik.
import com.anthropic.client.AnthropicClient;
import com.anthropic.client.okhttp.AnthropicOkHttpClient;
import com.anthropic.core.JsonValue;
import com.anthropic.models.messages.ContentBlockParam;
import com.anthropic.models.messages.Message;
import com.anthropic.models.messages.MessageCreateParams;
import com.anthropic.models.messages.MessageParam;
import com.anthropic.models.messages.Model;
import com.anthropic.models.messages.StopReason;
import com.anthropic.models.messages.Tool;
import com.anthropic.models.messages.Tool.InputSchema;
import com.anthropic.models.messages.ToolChoiceAuto;
import com.anthropic.models.messages.ToolResultBlockParam;
import com.anthropic.models.messages.ToolUseBlock;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
String runTool(ToolUseBlock toolUse) {
// Input alat mentah berupa objek JSON; baca field-nya sebagai map.
Map input = (Map) toolUse._input().asObject().get();
if (toolUse.name().equals("create_calendar_event")) {
String title = input.containsKey("title") ? input.get("title").asStringOrThrow() : "";
return "{\"event_id\": \"evt_123\", \"status\": \"created\", \"title\": \"" + title + "\"}";
}
return "{\"error\": \"Unknown tool: " + toolUse.name() + "\"}";
}
void main() {
AnthropicClient client = AnthropicOkHttpClient.fromEnv();
Tool calendarTool = Tool.builder()
.name("create_calendar_event")
.description("Create a calendar event with attendees and optional recurrence.")
.inputSchema(InputSchema.builder()
.properties(JsonValue.from(Map.of(
"title", Map.of("type", "string"),
"start", Map.of("type", "string", "format", "date-time"),
"end", Map.of("type", "string", "format", "date-time"),
"attendees", Map.of(
"type", "array",
"items", Map.of("type", "string", "format", "email")
),
"recurrence", Map.of(
"type", "object",
"properties", Map.of(
"frequency", Map.of("enum", List.of("daily", "weekly", "monthly")),
"count", Map.of("type", "integer", "minimum", 1)
)
)
)))
.required(List.of("title", "start", "end"))
.build())
.build();
ToolChoiceAuto toolChoice = ToolChoiceAuto.builder()
.disableParallelToolUse(true)
.build();
// Simpan seluruh riwayat percakapan dalam list agar tiap giliran melihat konteks sebelumnya.
List messages = new ArrayList<>();
messages.add(MessageParam.builder()
.role(MessageParam.Role.USER)
.content("Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com.")
.build());
Message response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.toolChoice(toolChoice)
.messages(messages)
.build());
// Ulangi hingga Claude berhenti meminta alat. Tiap iterasi menjalankan alat yang
// diminta, menambahkan hasilnya ke riwayat, lalu meminta Claude melanjutkan.
while (response.stopReason().isPresent()
&& response.stopReason().get().equals(StopReason.TOOL_USE)) {
ToolUseBlock toolUse = response.content().stream()
.flatMap(block -> block.toolUse().stream())
.findFirst()
.orElseThrow();
String result = runTool(toolUse);
messages.add(response.toParam());
messages.add(MessageParam.builder()
.role(MessageParam.Role.USER)
.contentOfBlockParams(List.of(ContentBlockParam.ofToolResult(
ToolResultBlockParam.builder()
.toolUseId(toolUse.id())
.content(result)
.build())))
.build());
response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.toolChoice(toolChoice)
.messages(messages)
.build());
}
response.content().stream()
.flatMap(block -> block.text().stream())
.forEach(textBlock -> IO.println(textBlock.text()));
}
```
```php PHP
'create_calendar_event',
'description' => 'Create a calendar event with attendees and optional recurrence.',
'input_schema' => [
'type' => 'object',
'properties' => [
'title' => ['type' => 'string'],
'start' => ['type' => 'string', 'format' => 'date-time'],
'end' => ['type' => 'string', 'format' => 'date-time'],
'attendees' => [
'type' => 'array',
'items' => ['type' => 'string', 'format' => 'email'],
],
'recurrence' => [
'type' => 'object',
'properties' => [
'frequency' => ['enum' => ['daily', 'weekly', 'monthly']],
'count' => ['type' => 'integer', 'minimum' => 1],
],
],
],
'required' => ['title', 'start', 'end'],
],
],
];
function runTool(string $name, array $input): string
{
if ($name === 'create_calendar_event') {
return json_encode([
'event_id' => 'evt_123',
'status' => 'created',
'title' => $input['title'],
]);
}
return json_encode(['error' => "Unknown tool: {$name}"]);
}
$toolChoice = ToolChoiceAuto::with(disableParallelToolUse: true);
// Simpan seluruh riwayat percakapan dalam array agar setiap giliran melihat konteks sebelumnya.
$messages = [
[
'role' => 'user',
'content' => 'Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com.',
],
];
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
toolChoice: $toolChoice,
messages: $messages,
);
// Ulangi hingga Claude berhenti meminta alat. Setiap iterasi menjalankan alat
// yang diminta, menambahkan hasilnya ke riwayat, lalu meminta Claude melanjutkan.
while ($response->stopReason === 'tool_use') {
$toolUse = null;
foreach ($response->content as $block) {
if ($block->type === 'tool_use') {
$toolUse = $block;
break;
}
}
$result = runTool($toolUse->name, $toolUse->input);
$messages[] = ['role' => 'assistant', 'content' => $response->content];
$messages[] = [
'role' => 'user',
'content' => [
[
'type' => 'tool_result',
'tool_use_id' => $toolUse->id,
'content' => $result,
],
],
];
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
toolChoice: $toolChoice,
messages: $messages,
);
}
foreach ($response->content as $block) {
if ($block->type === 'text') {
echo $block->text, "\n";
}
}
```
```ruby Ruby
# Ring 2: Loop agentik.
require "anthropic"
client = Anthropic::Client.new
tools = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: {type: "string"},
start: {type: "string", format: "date-time"},
end: {type: "string", format: "date-time"},
attendees: {
type: "array",
items: {type: "string", format: "email"}
},
recurrence: {
type: "object",
properties: {
frequency: {enum: ["daily", "weekly", "monthly"]},
count: {type: "integer", minimum: 1}
}
}
},
required: ["title", "start", "end"]
}
}
]
def run_tool(name, input)
case name
when "create_calendar_event"
JSON.generate({event_id: "evt_123", status: "created", title: input[:title]})
else
JSON.generate({error: "Unknown tool: #{name}"})
end
end
tool_choice = {type: "auto", disable_parallel_tool_use: true}
# Simpan seluruh riwayat percakapan dalam array agar setiap giliran melihat konteks sebelumnya.
messages = [
{
role: "user",
content: "Schedule a weekly team standup every Monday at 9am for the next 4 weeks, starting Monday, March 30, 2026. Invite the whole team: alice@example.com, bob@example.com, carol@example.com."
}
]
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
tool_choice: tool_choice,
messages: messages
)
# Ulangi hingga Claude berhenti meminta alat. Setiap iterasi menjalankan alat
# yang diminta, menambahkan hasilnya ke riwayat, lalu meminta Claude melanjutkan.
while response.stop_reason == :tool_use
tool_use = response.content.find { |block| block.type == :tool_use }
result = run_tool(tool_use.name, tool_use.input)
messages << {role: "assistant", content: response.content}
messages << {
role: "user",
content: [
{
type: "tool_result",
tool_use_id: tool_use.id,
content: result
}
]
}
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
tool_choice: tool_choice,
messages: messages
)
end
response.content.each do |block|
puts block.text if block.type == :text
end
```
**Apa yang diharapkan**
```text Output wrap
I've set up your weekly team standup for the next 4 Mondays at 9am with Alice, Bob, and Carol invited.
```
Loop mungkin berjalan sekali atau beberapa kali tergantung pada bagaimana Claude memecah tugasnya. Kode Anda tidak perlu lagi mengetahuinya terlebih dahulu.
## Cincin 3: Banyak alat, panggilan paralel
Agen jarang hanya memiliki satu kemampuan. Tambahkan alat kedua, `list_calendar_events`, agar Claude dapat memeriksa jadwal yang ada sebelum membuat sesuatu yang baru.
Ketika Claude memiliki beberapa panggilan alat independen untuk dilakukan, Claude mungkin mengembalikan beberapa blok `tool_use` dalam satu respons. Loop Anda perlu memproses semuanya dan mengirimkan kembali semua hasil bersama-sama dalam satu pesan pengguna. Iterasi setiap blok `tool_use` dalam `response.content`, bukan hanya yang pertama.
```bash cURL
#!/bin/bash
# Ring 3: Multiple tools, parallel calls.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```bash CLI
#!/usr/bin/env bash
# Ring 3: Multiple tools, parallel calls.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```python Python
# Ring 3: Beberapa alat, panggilan paralel.
import json
import anthropic
client = anthropic.Anthropic()
tools = [
{
"name": "create_calendar_event",
"description": "Create a calendar event with attendees and optional recurrence.",
"input_schema": {
"type": "object",
"properties": {
"title": {"type": "string"},
"start": {"type": "string", "format": "date-time"},
"end": {"type": "string", "format": "date-time"},
"attendees": {
"type": "array",
"items": {"type": "string", "format": "email"},
},
"recurrence": {
"type": "object",
"properties": {
"frequency": {"enum": ["daily", "weekly", "monthly"]},
"count": {"type": "integer", "minimum": 1},
},
},
},
"required": ["title", "start", "end"],
},
},
{
"name": "list_calendar_events",
"description": "List all calendar events on a given date.",
"input_schema": {
"type": "object",
"properties": {
"date": {"type": "string", "format": "date"},
},
"required": ["date"],
},
},
]
def run_tool(name, tool_input):
if name == "create_calendar_event":
return {
"event_id": "evt_123",
"status": "created",
"title": tool_input["title"],
}
if name == "list_calendar_events":
return {
"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]
}
return {"error": f"Unknown tool: {name}"}
messages = [
{
"role": "user",
"content": "Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.",
}
]
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
messages=messages,
)
while response.stop_reason == "tool_use":
# Satu respons dapat berisi beberapa blok tool_use. Proses semuanya
# dan kembalikan semua hasilnya sekaligus dalam satu pesan user.
tool_results = []
for block in response.content:
if block.type == "tool_use":
result = run_tool(block.name, block.input)
tool_results.append(
{
"type": "tool_result",
"tool_use_id": block.id,
"content": json.dumps(result),
}
)
messages.append({"role": "assistant", "content": response.content})
messages.append({"role": "user", "content": tool_results})
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
messages=messages,
)
final_text = next(block for block in response.content if block.type == "text")
print(final_text.text)
```
```typescript TypeScript
// Ring 3: Beberapa alat, panggilan paralel.
import Anthropic from "@anthropic-ai/sdk";
const client = new Anthropic();
const tools: Anthropic.Tool[] = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: { type: "string" },
start: { type: "string", format: "date-time" },
end: { type: "string", format: "date-time" },
attendees: {
type: "array",
items: { type: "string", format: "email" }
},
recurrence: {
type: "object",
properties: {
frequency: { enum: ["daily", "weekly", "monthly"] },
count: { type: "integer", minimum: 1 }
}
}
},
required: ["title", "start", "end"]
}
},
{
name: "list_calendar_events",
description: "List all calendar events on a given date.",
input_schema: {
type: "object",
properties: {
date: { type: "string", format: "date" }
},
required: ["date"]
}
}
];
function runTool(name: string, input: Record) {
if (name === "create_calendar_event") {
return { event_id: "evt_123", status: "created", title: input.title };
}
if (name === "list_calendar_events") {
return {
events: [{ title: "Existing meeting", start: "14:00", end: "15:00" }]
};
}
return { error: `Unknown tool: ${name}` };
}
const messages: Anthropic.MessageParam[] = [
{
role: "user",
content:
"Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts."
}
];
let response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
messages
});
while (response.stop_reason === "tool_use") {
// Satu respons dapat berisi beberapa blok tool_use. Proses semuanya
// lalu kembalikan semua hasilnya sekaligus dalam satu pesan user.
const toolResults: Anthropic.ToolResultBlockParam[] = [];
for (const block of response.content) {
if (block.type === "tool_use") {
const result = runTool(block.name, block.input as Record);
toolResults.push({
type: "tool_result",
tool_use_id: block.id,
content: JSON.stringify(result)
});
}
}
messages.push({ role: "assistant", content: response.content });
messages.push({ role: "user", content: toolResults });
response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
messages
});
}
for (const block of response.content) {
if (block.type === "text") {
console.log(block.text);
}
}
```
```csharp C#
// Ring 3: Beberapa alat, panggilan paralel.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Threading.Tasks;
using Anthropic;
using Anthropic.Models.Messages;
AnthropicClient client = new();
List tools =
[
new ToolUnion(new Tool()
{
Name = "create_calendar_event",
Description = "Create a calendar event with attendees and optional recurrence.",
InputSchema = new InputSchema()
{
Properties = new Dictionary
{
["title"] = JsonSerializer.SerializeToElement(new { type = "string" }),
["start"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["end"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["attendees"] = JsonSerializer.SerializeToElement(new
{
type = "array",
items = new { type = "string", format = "email" },
}),
["recurrence"] = JsonSerializer.SerializeToElement(new
{
type = "object",
properties = new
{
frequency = new { @enum = new[] { "daily", "weekly", "monthly" } },
count = new { type = "integer", minimum = 1 },
},
}),
},
Required = ["title", "start", "end"],
},
}),
new ToolUnion(new Tool()
{
Name = "list_calendar_events",
Description = "List all calendar events on a given date.",
InputSchema = new InputSchema()
{
Properties = new Dictionary
{
["date"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date" }),
},
Required = ["date"],
},
}),
];
string RunTool(ToolUseBlock toolUse)
{
if (toolUse.Name == "create_calendar_event")
{
var title = toolUse.Input.TryGetValue("title", out var t) ? t.GetString() : "";
return JsonSerializer.Serialize(new { event_id = "evt_123", status = "created", title });
}
if (toolUse.Name == "list_calendar_events")
{
return """{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}""";
}
return JsonSerializer.Serialize(new { error = $"Unknown tool: {toolUse.Name}" });
}
List messages =
[
new()
{
Role = Role.User,
Content = "Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.",
},
];
var response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
Messages = messages,
});
while (response.StopReason == StopReason.ToolUse)
{
// Satu respons dapat berisi beberapa blok tool_use. Proses semua blok
// tersebut dan kembalikan semua hasilnya sekaligus dalam satu pesan user.
List toolResults = [];
foreach (var block in response.Content)
{
if (block.TryPickToolUse(out var toolUse))
{
toolResults.Add(new ContentBlockParam(new ToolResultBlockParam()
{
ToolUseID = toolUse.ID,
Content = RunTool(toolUse),
}));
}
}
messages.Add(new()
{
Role = Role.Assistant,
Content = response.Content.Select(block => new ContentBlockParam(block.Json)).ToList(),
});
messages.Add(new() { Role = Role.User, Content = new MessageParamContent(toolResults) });
response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
Messages = messages,
});
}
foreach (var block in response.Content)
{
if (block.TryPickText(out var text))
{
Console.WriteLine(text.Text);
}
}
```
```go Go
// Ring 3: Beberapa alat, panggilan paralel.
package main
import (
"context"
"encoding/json"
"fmt"
"log"
"github.com/anthropics/anthropic-sdk-go"
)
func runTool(name string, input map[string]any) string {
if name == "create_calendar_event" {
title, _ := input["title"].(string)
return fmt.Sprintf(`{"event_id": "evt_123", "status": "created", "title": %q}`, title)
}
if name == "list_calendar_events" {
return `{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}`
}
return fmt.Sprintf(`{"error": "Unknown tool: %s"}`, name)
}
func main() {
client := anthropic.NewClient()
ctx := context.Background()
tools := []anthropic.ToolUnionParam{
{OfTool: &anthropic.ToolParam{
Name: "create_calendar_event",
Description: anthropic.String("Create a calendar event with attendees and optional recurrence."),
InputSchema: anthropic.ToolInputSchemaParam{
Properties: map[string]any{
"title": map[string]any{"type": "string"},
"start": map[string]any{"type": "string", "format": "date-time"},
"end": map[string]any{"type": "string", "format": "date-time"},
"attendees": map[string]any{
"type": "array",
"items": map[string]any{"type": "string", "format": "email"},
},
"recurrence": map[string]any{
"type": "object",
"properties": map[string]any{
"frequency": map[string]any{"enum": []string{"daily", "weekly", "monthly"}},
"count": map[string]any{"type": "integer", "minimum": 1},
},
},
},
Required: []string{"title", "start", "end"},
},
}},
{OfTool: &anthropic.ToolParam{
Name: "list_calendar_events",
Description: anthropic.String("List all calendar events on a given date."),
InputSchema: anthropic.ToolInputSchemaParam{
Properties: map[string]any{
"date": map[string]any{"type": "string", "format": "date"},
},
Required: []string{"date"},
},
}},
}
messages := []anthropic.MessageParam{
anthropic.NewUserMessage(anthropic.NewTextBlock(
"Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.",
)),
}
response, err := client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
Messages: messages,
})
if err != nil {
log.Fatal(err)
}
for response.StopReason == "tool_use" {
// Satu respons dapat berisi beberapa blok tool_use. Proses semuanya
// lalu kembalikan semua hasilnya sekaligus dalam satu pesan user.
var toolResults []anthropic.ContentBlockParamUnion
for _, block := range response.Content {
if block.Type == "tool_use" {
var input map[string]any
if err := json.Unmarshal(block.Input, &input); err != nil {
log.Fatal(err)
}
result := runTool(block.Name, input)
toolResults = append(toolResults, anthropic.NewToolResultBlock(block.ID, result, false))
}
}
var assistantContent []anthropic.ContentBlockParamUnion
for _, block := range response.Content {
assistantContent = append(assistantContent, block.ToParam())
}
messages = append(messages, anthropic.NewAssistantMessage(assistantContent...))
messages = append(messages, anthropic.NewUserMessage(toolResults...))
response, err = client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
Messages: messages,
})
if err != nil {
log.Fatal(err)
}
}
for _, block := range response.Content {
if block.Type == "text" {
fmt.Println(block.Text)
}
}
}
```
```java Java
// Ring 3: Beberapa alat, panggilan paralel.
import com.anthropic.client.AnthropicClient;
import com.anthropic.client.okhttp.AnthropicOkHttpClient;
import com.anthropic.core.JsonValue;
import com.anthropic.models.messages.ContentBlock;
import com.anthropic.models.messages.ContentBlockParam;
import com.anthropic.models.messages.Message;
import com.anthropic.models.messages.MessageCreateParams;
import com.anthropic.models.messages.MessageParam;
import com.anthropic.models.messages.Model;
import com.anthropic.models.messages.StopReason;
import com.anthropic.models.messages.Tool;
import com.anthropic.models.messages.Tool.InputSchema;
import com.anthropic.models.messages.ToolResultBlockParam;
import com.anthropic.models.messages.ToolUseBlock;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
String runTool(ToolUseBlock toolUse) {
// Input alat mentah berupa objek JSON; baca field-nya sebagai map.
Map input = (Map) toolUse._input().asObject().get();
if (toolUse.name().equals("create_calendar_event")) {
String title = input.containsKey("title") ? input.get("title").asStringOrThrow() : "";
return "{\"event_id\": \"evt_123\", \"status\": \"created\", \"title\": \"" + title + "\"}";
}
if (toolUse.name().equals("list_calendar_events")) {
return "{\"events\": [{\"title\": \"Existing meeting\", \"start\": \"14:00\", \"end\": \"15:00\"}]}";
}
return "{\"error\": \"Unknown tool: " + toolUse.name() + "\"}";
}
void main() {
AnthropicClient client = AnthropicOkHttpClient.fromEnv();
Tool calendarTool = Tool.builder()
.name("create_calendar_event")
.description("Create a calendar event with attendees and optional recurrence.")
.inputSchema(InputSchema.builder()
.properties(JsonValue.from(Map.of(
"title", Map.of("type", "string"),
"start", Map.of("type", "string", "format", "date-time"),
"end", Map.of("type", "string", "format", "date-time"),
"attendees", Map.of(
"type", "array",
"items", Map.of("type", "string", "format", "email")
),
"recurrence", Map.of(
"type", "object",
"properties", Map.of(
"frequency", Map.of("enum", List.of("daily", "weekly", "monthly")),
"count", Map.of("type", "integer", "minimum", 1)
)
)
)))
.required(List.of("title", "start", "end"))
.build())
.build();
Tool listTool = Tool.builder()
.name("list_calendar_events")
.description("List all calendar events on a given date.")
.inputSchema(InputSchema.builder()
.properties(JsonValue.from(Map.of(
"date", Map.of("type", "string", "format", "date")
)))
.required(List.of("date"))
.build())
.build();
List messages = new ArrayList<>();
messages.add(MessageParam.builder()
.role(MessageParam.Role.USER)
.content("Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.")
.build());
Message response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.addTool(listTool)
.messages(messages)
.build());
while (response.stopReason().isPresent()
&& response.stopReason().get().equals(StopReason.TOOL_USE)) {
// Satu respons dapat berisi beberapa blok tool_use. Proses semuanya
// dan kembalikan semua hasil sekaligus dalam satu pesan user.
List toolResults = new ArrayList<>();
for (ContentBlock block : response.content()) {
if (block.toolUse().isPresent()) {
ToolUseBlock toolUse = block.toolUse().get();
toolResults.add(ContentBlockParam.ofToolResult(
ToolResultBlockParam.builder()
.toolUseId(toolUse.id())
.content(runTool(toolUse))
.build()));
}
}
messages.add(response.toParam());
messages.add(MessageParam.builder()
.role(MessageParam.Role.USER)
.contentOfBlockParams(toolResults)
.build());
response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.addTool(listTool)
.messages(messages)
.build());
}
response.content().stream()
.flatMap(block -> block.text().stream())
.forEach(textBlock -> IO.println(textBlock.text()));
}
```
```php PHP
'create_calendar_event',
'description' => 'Create a calendar event with attendees and optional recurrence.',
'input_schema' => [
'type' => 'object',
'properties' => [
'title' => ['type' => 'string'],
'start' => ['type' => 'string', 'format' => 'date-time'],
'end' => ['type' => 'string', 'format' => 'date-time'],
'attendees' => [
'type' => 'array',
'items' => ['type' => 'string', 'format' => 'email'],
],
'recurrence' => [
'type' => 'object',
'properties' => [
'frequency' => ['enum' => ['daily', 'weekly', 'monthly']],
'count' => ['type' => 'integer', 'minimum' => 1],
],
],
],
'required' => ['title', 'start', 'end'],
],
],
[
'name' => 'list_calendar_events',
'description' => 'List all calendar events on a given date.',
'input_schema' => [
'type' => 'object',
'properties' => [
'date' => ['type' => 'string', 'format' => 'date'],
],
'required' => ['date'],
],
],
];
function runTool(string $name, array $input): string
{
if ($name === 'create_calendar_event') {
return json_encode([
'event_id' => 'evt_123',
'status' => 'created',
'title' => $input['title'],
]);
}
if ($name === 'list_calendar_events') {
return json_encode([
'events' => [['title' => 'Existing meeting', 'start' => '14:00', 'end' => '15:00']],
]);
}
return json_encode(['error' => "Unknown tool: {$name}"]);
}
$messages = [
[
'role' => 'user',
'content' => 'Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.',
],
];
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
messages: $messages,
);
while ($response->stopReason === 'tool_use') {
// Satu respons dapat berisi beberapa blok tool_use. Proses semua blok
// tersebut dan kembalikan semua hasilnya sekaligus dalam satu pesan user.
$toolResults = [];
foreach ($response->content as $block) {
if ($block->type === 'tool_use') {
$toolResults[] = [
'type' => 'tool_result',
'tool_use_id' => $block->id,
'content' => runTool($block->name, $block->input),
];
}
}
$messages[] = ['role' => 'assistant', 'content' => $response->content];
$messages[] = ['role' => 'user', 'content' => $toolResults];
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
messages: $messages,
);
}
foreach ($response->content as $block) {
if ($block->type === 'text') {
echo $block->text, "\n";
}
}
```
```ruby Ruby
# Ring 3: Beberapa alat, panggilan paralel.
require "anthropic"
client = Anthropic::Client.new
tools = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: {type: "string"},
start: {type: "string", format: "date-time"},
end: {type: "string", format: "date-time"},
attendees: {
type: "array",
items: {type: "string", format: "email"}
},
recurrence: {
type: "object",
properties: {
frequency: {enum: ["daily", "weekly", "monthly"]},
count: {type: "integer", minimum: 1}
}
}
},
required: ["title", "start", "end"]
}
},
{
name: "list_calendar_events",
description: "List all calendar events on a given date.",
input_schema: {
type: "object",
properties: {
date: {type: "string", format: "date"}
},
required: ["date"]
}
}
]
def run_tool(name, input)
case name
when "create_calendar_event"
JSON.generate({event_id: "evt_123", status: "created", title: input[:title]})
when "list_calendar_events"
JSON.generate({events: [{title: "Existing meeting", start: "14:00", end: "15:00"}]})
else
JSON.generate({error: "Unknown tool: #{name}"})
end
end
messages = [
{
role: "user",
content: "Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts."
}
]
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
messages: messages
)
while response.stop_reason == :tool_use
# Satu respons dapat berisi beberapa blok tool_use. Proses semua blok
# tersebut dan kembalikan semua hasilnya sekaligus dalam satu pesan user.
tool_results = response.content.select { |block| block.type == :tool_use }.map do |tool_use|
{
type: "tool_result",
tool_use_id: tool_use.id,
content: run_tool(tool_use.name, tool_use.input)
}
end
messages << {role: "assistant", content: response.content}
messages << {role: "user", content: tool_results}
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
messages: messages
)
end
response.content.each do |block|
puts block.text if block.type == :text
end
```
**Apa yang diharapkan**
```text Output wrap
I checked your calendar for Monday, March 30 and found an existing meeting from 2pm to 3pm. I've scheduled the planning session for 10am to 11am to avoid the conflict.
```
Untuk informasi lebih lanjut tentang eksekusi konkuren dan jaminan urutan, lihat [Penggunaan alat paralel](https://platform.claude.com/docs/id/agents-and-tools/tool-use/parallel-tool-use).
## Cincin 4: Penanganan error
Alat bisa gagal. API kalender mungkin menolak acara dengan terlalu banyak peserta, atau sebuah tanggal mungkin salah format. Ketika alat memunculkan error, kirimkan pesan error kembali dengan `is_error: true` alih-alih membuat program crash. Claude membaca error tersebut dan dapat mencoba lagi dengan input yang diperbaiki, meminta klarifikasi kepada pengguna, atau menjelaskan keterbatasannya.
```bash cURL
#!/bin/bash
# Ring 4: Error handling.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```bash CLI
#!/usr/bin/env bash
# Ring 4: Error handling.
# This workflow needs more logic than a single shell command.
# Use the Claude SDK to run it.
```
```python Python
# Ring 4: Penanganan error.
import json
import anthropic
client = anthropic.Anthropic()
tools = [
{
"name": "create_calendar_event",
"description": "Create a calendar event with attendees and optional recurrence.",
"input_schema": {
"type": "object",
"properties": {
"title": {"type": "string"},
"start": {"type": "string", "format": "date-time"},
"end": {"type": "string", "format": "date-time"},
"attendees": {
"type": "array",
"items": {"type": "string", "format": "email"},
},
"recurrence": {
"type": "object",
"properties": {
"frequency": {"enum": ["daily", "weekly", "monthly"]},
"count": {"type": "integer", "minimum": 1},
},
},
},
"required": ["title", "start", "end"],
},
},
{
"name": "list_calendar_events",
"description": "List all calendar events on a given date.",
"input_schema": {
"type": "object",
"properties": {
"date": {"type": "string", "format": "date"},
},
"required": ["date"],
},
},
]
def run_tool(name, tool_input):
if name == "create_calendar_event":
if "attendees" in tool_input and len(tool_input["attendees"]) > 10:
raise ValueError("Too many attendees (max 10)")
return {
"event_id": "evt_123",
"status": "created",
"title": tool_input["title"],
}
if name == "list_calendar_events":
return {
"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]
}
raise ValueError(f"Unknown tool: {name}")
messages = [
{
"role": "user",
"content": "Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: "
+ ", ".join(f"user{i}@example.com" for i in range(15)),
}
]
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
messages=messages,
)
while response.stop_reason == "tool_use":
tool_results = []
for block in response.content:
if block.type == "tool_use":
try:
result = run_tool(block.name, block.input)
tool_results.append(
{
"type": "tool_result",
"tool_use_id": block.id,
"content": json.dumps(result),
}
)
except Exception as exc:
# Beri sinyal kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
tool_results.append(
{
"type": "tool_result",
"tool_use_id": block.id,
"content": str(exc),
"is_error": True,
}
)
messages.append({"role": "assistant", "content": response.content})
messages.append({"role": "user", "content": tool_results})
response = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
tools=tools,
messages=messages,
)
final_text = next(block for block in response.content if block.type == "text")
print(final_text.text)
```
```typescript TypeScript
// Ring 4: Penanganan error.
import Anthropic from "@anthropic-ai/sdk";
const client = new Anthropic();
const tools: Anthropic.Tool[] = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: { type: "string" },
start: { type: "string", format: "date-time" },
end: { type: "string", format: "date-time" },
attendees: {
type: "array",
items: { type: "string", format: "email" }
},
recurrence: {
type: "object",
properties: {
frequency: { enum: ["daily", "weekly", "monthly"] },
count: { type: "integer", minimum: 1 }
}
}
},
required: ["title", "start", "end"]
}
},
{
name: "list_calendar_events",
description: "List all calendar events on a given date.",
input_schema: {
type: "object",
properties: {
date: { type: "string", format: "date" }
},
required: ["date"]
}
}
];
function runTool(name: string, input: Record) {
if (name === "create_calendar_event") {
const attendees = input.attendees as string[] | undefined;
if (attendees && attendees.length > 10) {
throw new Error("Too many attendees (max 10)");
}
return { event_id: "evt_123", status: "created", title: input.title };
}
if (name === "list_calendar_events") {
return {
events: [{ title: "Existing meeting", start: "14:00", end: "15:00" }]
};
}
throw new Error(`Unknown tool: ${name}`);
}
const emails = Array.from({ length: 15 }, (_, i) => `user${i}@example.com`).join(", ");
const messages: Anthropic.MessageParam[] = [
{
role: "user",
content: `Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: ${emails}`
}
];
let response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
messages
});
while (response.stop_reason === "tool_use") {
const toolResults: Anthropic.ToolResultBlockParam[] = [];
for (const block of response.content) {
if (block.type === "tool_use") {
try {
const result = runTool(block.name, block.input as Record);
toolResults.push({
type: "tool_result",
tool_use_id: block.id,
content: JSON.stringify(result)
});
} catch (err) {
// Tandai kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
toolResults.push({
type: "tool_result",
tool_use_id: block.id,
content: String(err),
is_error: true
});
}
}
}
messages.push({ role: "assistant", content: response.content });
messages.push({ role: "user", content: toolResults });
response = await client.messages.create({
model: "claude-opus-5-5",
max_tokens: 1024,
tools,
messages
});
}
for (const block of response.content) {
if (block.type === "text") {
console.log(block.text);
}
}
```
```csharp C#
// Ring 4: Penanganan error.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Threading.Tasks;
using Anthropic;
using Anthropic.Models.Messages;
AnthropicClient client = new();
List tools =
[
new ToolUnion(new Tool()
{
Name = "create_calendar_event",
Description = "Create a calendar event with attendees and optional recurrence.",
InputSchema = new InputSchema()
{
Properties = new Dictionary
{
["title"] = JsonSerializer.SerializeToElement(new { type = "string" }),
["start"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["end"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date-time" }),
["attendees"] = JsonSerializer.SerializeToElement(new
{
type = "array",
items = new { type = "string", format = "email" },
}),
["recurrence"] = JsonSerializer.SerializeToElement(new
{
type = "object",
properties = new
{
frequency = new { @enum = new[] { "daily", "weekly", "monthly" } },
count = new { type = "integer", minimum = 1 },
},
}),
},
Required = ["title", "start", "end"],
},
}),
new ToolUnion(new Tool()
{
Name = "list_calendar_events",
Description = "List all calendar events on a given date.",
InputSchema = new InputSchema()
{
Properties = new Dictionary
{
["date"] = JsonSerializer.SerializeToElement(new { type = "string", format = "date" }),
},
Required = ["date"],
},
}),
];
string RunTool(ToolUseBlock toolUse)
{
if (toolUse.Name == "create_calendar_event")
{
if (toolUse.Input.TryGetValue("attendees", out var attendees) && attendees.GetArrayLength() > 10)
{
throw new InvalidOperationException("Too many attendees (max 10)");
}
var title = toolUse.Input.TryGetValue("title", out var t) ? t.GetString() : "";
return JsonSerializer.Serialize(new { event_id = "evt_123", status = "created", title });
}
if (toolUse.Name == "list_calendar_events")
{
return """{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}""";
}
throw new InvalidOperationException($"Unknown tool: {toolUse.Name}");
}
// Buat request yang melebihi batas peserta alat agar jalur error dijalankan.
var emails = string.Join(", ", Enumerable.Range(0, 15).Select(i => $"user{i}@example.com"));
List messages =
[
new() { Role = Role.User, Content = $"Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: {emails}" },
];
var response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
Messages = messages,
});
while (response.StopReason == StopReason.ToolUse)
{
List toolResults = [];
foreach (var block in response.Content)
{
if (block.TryPickToolUse(out var toolUse))
{
ToolResultBlockParam toolResult;
try
{
toolResult = new ToolResultBlockParam() { ToolUseID = toolUse.ID, Content = RunTool(toolUse) };
}
catch (Exception e)
{
// Tandai kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
toolResult = new ToolResultBlockParam()
{
ToolUseID = toolUse.ID,
Content = e.Message,
IsError = true,
};
}
toolResults.Add(new ContentBlockParam(toolResult));
}
}
messages.Add(new()
{
Role = Role.Assistant,
Content = response.Content.Select(block => new ContentBlockParam(block.Json)).ToList(),
});
messages.Add(new() { Role = Role.User, Content = new MessageParamContent(toolResults) });
response = await client.Messages.Create(new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Tools = tools,
Messages = messages,
});
}
foreach (var block in response.Content)
{
if (block.TryPickText(out var text))
{
Console.WriteLine(text.Text);
}
}
```
```go Go
// Ring 4: Penanganan error.
package main
import (
"context"
"encoding/json"
"fmt"
"log"
"strings"
"github.com/anthropics/anthropic-sdk-go"
)
func runTool(name string, input map[string]any) (string, error) {
if name == "create_calendar_event" {
if attendees, ok := input["attendees"].([]any); ok && len(attendees) > 10 {
return "", fmt.Errorf("too many attendees (max 10)")
}
title, _ := input["title"].(string)
return fmt.Sprintf(`{"event_id": "evt_123", "status": "created", "title": %q}`, title), nil
}
if name == "list_calendar_events" {
return `{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}`, nil
}
return "", fmt.Errorf("unknown tool: %s", name)
}
func main() {
client := anthropic.NewClient()
ctx := context.Background()
tools := []anthropic.ToolUnionParam{
{OfTool: &anthropic.ToolParam{
Name: "create_calendar_event",
Description: anthropic.String("Create a calendar event with attendees and optional recurrence."),
InputSchema: anthropic.ToolInputSchemaParam{
Properties: map[string]any{
"title": map[string]any{"type": "string"},
"start": map[string]any{"type": "string", "format": "date-time"},
"end": map[string]any{"type": "string", "format": "date-time"},
"attendees": map[string]any{
"type": "array",
"items": map[string]any{"type": "string", "format": "email"},
},
"recurrence": map[string]any{
"type": "object",
"properties": map[string]any{
"frequency": map[string]any{"enum": []string{"daily", "weekly", "monthly"}},
"count": map[string]any{"type": "integer", "minimum": 1},
},
},
},
Required: []string{"title", "start", "end"},
},
}},
{OfTool: &anthropic.ToolParam{
Name: "list_calendar_events",
Description: anthropic.String("List all calendar events on a given date."),
InputSchema: anthropic.ToolInputSchemaParam{
Properties: map[string]any{
"date": map[string]any{"type": "string", "format": "date"},
},
Required: []string{"date"},
},
}},
}
// Buat request yang melebihi batas peserta alat agar jalur error dijalankan.
emails := make([]string, 15)
for i := range emails {
emails[i] = fmt.Sprintf("user%d@example.com", i)
}
messages := []anthropic.MessageParam{
anthropic.NewUserMessage(anthropic.NewTextBlock(
"Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: " + strings.Join(emails, ", "),
)),
}
response, err := client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
Messages: messages,
})
if err != nil {
log.Fatal(err)
}
for response.StopReason == "tool_use" {
var toolResults []anthropic.ContentBlockParamUnion
for _, block := range response.Content {
if block.Type == "tool_use" {
var input map[string]any
if err := json.Unmarshal(block.Input, &input); err != nil {
log.Fatal(err)
}
result, toolErr := runTool(block.Name, input)
if toolErr != nil {
// Tandai kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
toolResults = append(toolResults, anthropic.NewToolResultBlock(block.ID, toolErr.Error(), true))
} else {
toolResults = append(toolResults, anthropic.NewToolResultBlock(block.ID, result, false))
}
}
}
var assistantContent []anthropic.ContentBlockParamUnion
for _, block := range response.Content {
assistantContent = append(assistantContent, block.ToParam())
}
messages = append(messages, anthropic.NewAssistantMessage(assistantContent...))
messages = append(messages, anthropic.NewUserMessage(toolResults...))
response, err = client.Messages.New(ctx, anthropic.MessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Tools: tools,
Messages: messages,
})
if err != nil {
log.Fatal(err)
}
}
for _, block := range response.Content {
if block.Type == "text" {
fmt.Println(block.Text)
}
}
}
```
```java Java
// Ring 4: Penanganan error.
import com.anthropic.client.AnthropicClient;
import com.anthropic.client.okhttp.AnthropicOkHttpClient;
import com.anthropic.core.JsonValue;
import com.anthropic.models.messages.ContentBlock;
import com.anthropic.models.messages.ContentBlockParam;
import com.anthropic.models.messages.Message;
import com.anthropic.models.messages.MessageCreateParams;
import com.anthropic.models.messages.MessageParam;
import com.anthropic.models.messages.Model;
import com.anthropic.models.messages.StopReason;
import com.anthropic.models.messages.Tool;
import com.anthropic.models.messages.Tool.InputSchema;
import com.anthropic.models.messages.ToolResultBlockParam;
import com.anthropic.models.messages.ToolUseBlock;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
String runTool(ToolUseBlock toolUse) {
// Input alat mentah berupa objek JSON; baca field-nya sebagai map.
Map input = (Map) toolUse._input().asObject().get();
if (toolUse.name().equals("create_calendar_event")) {
int attendeeCount = input.containsKey("attendees")
? ((List) input.get("attendees").asArray().get()).size()
: 0;
if (attendeeCount > 10) {
throw new IllegalArgumentException("Too many attendees (max 10)");
}
String title = input.containsKey("title") ? input.get("title").asStringOrThrow() : "";
return "{\"event_id\": \"evt_123\", \"status\": \"created\", \"title\": \"" + title + "\"}";
}
if (toolUse.name().equals("list_calendar_events")) {
return "{\"events\": [{\"title\": \"Existing meeting\", \"start\": \"14:00\", \"end\": \"15:00\"}]}";
}
throw new IllegalArgumentException("Unknown tool: " + toolUse.name());
}
void main() {
AnthropicClient client = AnthropicOkHttpClient.fromEnv();
Tool calendarTool = Tool.builder()
.name("create_calendar_event")
.description("Create a calendar event with attendees and optional recurrence.")
.inputSchema(InputSchema.builder()
.properties(JsonValue.from(Map.of(
"title", Map.of("type", "string"),
"start", Map.of("type", "string", "format", "date-time"),
"end", Map.of("type", "string", "format", "date-time"),
"attendees", Map.of(
"type", "array",
"items", Map.of("type", "string", "format", "email")
),
"recurrence", Map.of(
"type", "object",
"properties", Map.of(
"frequency", Map.of("enum", List.of("daily", "weekly", "monthly")),
"count", Map.of("type", "integer", "minimum", 1)
)
)
)))
.required(List.of("title", "start", "end"))
.build())
.build();
Tool listTool = Tool.builder()
.name("list_calendar_events")
.description("List all calendar events on a given date.")
.inputSchema(InputSchema.builder()
.properties(JsonValue.from(Map.of(
"date", Map.of("type", "string", "format", "date")
)))
.required(List.of("date"))
.build())
.build();
// Buat request yang melebihi batas peserta alat agar jalur error dijalankan.
String emails = IntStream.range(0, 15)
.mapToObj(i -> "user" + i + "@example.com")
.collect(Collectors.joining(", "));
List messages = new ArrayList<>();
messages.add(MessageParam.builder()
.role(MessageParam.Role.USER)
.content("Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: " + emails)
.build());
Message response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.addTool(listTool)
.messages(messages)
.build());
while (response.stopReason().isPresent()
&& response.stopReason().get().equals(StopReason.TOOL_USE)) {
List toolResults = new ArrayList<>();
for (ContentBlock block : response.content()) {
if (block.toolUse().isPresent()) {
ToolUseBlock toolUse = block.toolUse().get();
ToolResultBlockParam.Builder resultBuilder = ToolResultBlockParam.builder()
.toolUseId(toolUse.id());
try {
resultBuilder.content(runTool(toolUse));
} catch (Exception e) {
// Tandai kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
resultBuilder.content(e.getMessage()).isError(true);
}
toolResults.add(ContentBlockParam.ofToolResult(resultBuilder.build()));
}
}
messages.add(response.toParam());
messages.add(MessageParam.builder()
.role(MessageParam.Role.USER)
.contentOfBlockParams(toolResults)
.build());
response = client.messages().create(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024L)
.addTool(calendarTool)
.addTool(listTool)
.messages(messages)
.build());
}
response.content().stream()
.flatMap(block -> block.text().stream())
.forEach(textBlock -> IO.println(textBlock.text()));
}
```
```php PHP
'create_calendar_event',
'description' => 'Create a calendar event with attendees and optional recurrence.',
'input_schema' => [
'type' => 'object',
'properties' => [
'title' => ['type' => 'string'],
'start' => ['type' => 'string', 'format' => 'date-time'],
'end' => ['type' => 'string', 'format' => 'date-time'],
'attendees' => [
'type' => 'array',
'items' => ['type' => 'string', 'format' => 'email'],
],
'recurrence' => [
'type' => 'object',
'properties' => [
'frequency' => ['enum' => ['daily', 'weekly', 'monthly']],
'count' => ['type' => 'integer', 'minimum' => 1],
],
],
],
'required' => ['title', 'start', 'end'],
],
],
[
'name' => 'list_calendar_events',
'description' => 'List all calendar events on a given date.',
'input_schema' => [
'type' => 'object',
'properties' => [
'date' => ['type' => 'string', 'format' => 'date'],
],
'required' => ['date'],
],
],
];
function runTool(string $name, array $input): string
{
if ($name === 'create_calendar_event') {
if (count($input['attendees'] ?? []) > 10) {
throw new \InvalidArgumentException('Too many attendees (max 10)');
}
return json_encode([
'event_id' => 'evt_123',
'status' => 'created',
'title' => $input['title'],
]);
}
if ($name === 'list_calendar_events') {
return json_encode([
'events' => [['title' => 'Existing meeting', 'start' => '14:00', 'end' => '15:00']],
]);
}
throw new \InvalidArgumentException("Unknown tool: {$name}");
}
// Buat request yang melebihi batas peserta alat agar jalur error dijalankan.
$emails = array_map(fn (int $i): string => "user{$i}@example.com", range(0, 14));
$messages = [
[
'role' => 'user',
'content' => 'Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: ' . implode(', ', $emails),
],
];
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
messages: $messages,
);
while ($response->stopReason === 'tool_use') {
$toolResults = [];
foreach ($response->content as $block) {
if ($block->type === 'tool_use') {
try {
$toolResults[] = [
'type' => 'tool_result',
'tool_use_id' => $block->id,
'content' => runTool($block->name, $block->input),
];
} catch (\Exception $e) {
// Tandai kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
$toolResults[] = [
'type' => 'tool_result',
'tool_use_id' => $block->id,
'content' => $e->getMessage(),
'is_error' => true,
];
}
}
}
$messages[] = ['role' => 'assistant', 'content' => $response->content];
$messages[] = ['role' => 'user', 'content' => $toolResults];
$response = $client->messages->create(
model: 'claude-opus-5-5',
maxTokens: 1024,
tools: $tools,
messages: $messages,
);
}
foreach ($response->content as $block) {
if ($block->type === 'text') {
echo $block->text, "\n";
}
}
```
```ruby Ruby
# Ring 4: Penanganan error.
require "anthropic"
client = Anthropic::Client.new
tools = [
{
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
input_schema: {
type: "object",
properties: {
title: {type: "string"},
start: {type: "string", format: "date-time"},
end: {type: "string", format: "date-time"},
attendees: {
type: "array",
items: {type: "string", format: "email"}
},
recurrence: {
type: "object",
properties: {
frequency: {enum: ["daily", "weekly", "monthly"]},
count: {type: "integer", minimum: 1}
}
}
},
required: ["title", "start", "end"]
}
},
{
name: "list_calendar_events",
description: "List all calendar events on a given date.",
input_schema: {
type: "object",
properties: {
date: {type: "string", format: "date"}
},
required: ["date"]
}
}
]
def run_tool(name, input)
case name
when "create_calendar_event"
attendees = input[:attendees]
raise ArgumentError, "Too many attendees (max 10)" if attendees && attendees.length > 10
JSON.generate({event_id: "evt_123", status: "created", title: input[:title]})
when "list_calendar_events"
JSON.generate({events: [{title: "Existing meeting", start: "14:00", end: "15:00"}]})
else
raise ArgumentError, "Unknown tool: #{name}"
end
end
# Buat request yang melebihi batas peserta alat agar jalur error dijalankan.
emails = (0...15).map { |i| "user#{i}@example.com" }
messages = [
{
role: "user",
content: "Schedule a one-hour all-hands on Monday, March 30, 2026 at 10am with everyone: #{emails.join(", ")}"
}
]
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
messages: messages
)
while response.stop_reason == :tool_use
tool_results = response.content.select { |block| block.type == :tool_use }.map do |tool_use|
begin
{
type: "tool_result",
tool_use_id: tool_use.id,
content: run_tool(tool_use.name, tool_use.input)
}
rescue => e
# Tandai kegagalan agar Claude dapat mencoba lagi atau meminta klarifikasi.
{
type: "tool_result",
tool_use_id: tool_use.id,
content: e.message,
is_error: true
}
end
end
messages << {role: "assistant", content: response.content}
messages << {role: "user", content: tool_results}
response = client.messages.create(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: tools,
messages: messages
)
end
response.content.each do |block|
puts block.text if block.type == :text
end
```
**Apa yang diharapkan**
```text Output wrap
I tried to schedule the all-hands but the calendar only allows 10 attendees per event. I can split this into two sessions, or you can let me know which 10 people to prioritize.
```
Flag `is_error` adalah satu-satunya perbedaan dari hasil yang berhasil. Claude melihat flag dan teks error tersebut, lalu merespons sesuai dengannya. Lihat [Menangani panggilan alat](https://platform.claude.com/docs/id/agents-and-tools/tool-use/handle-tool-calls) untuk referensi penanganan error yang lengkap.
## Cincin 5: Abstraksi SDK Tool Runner
Cincin 2 hingga 4 menulis loop yang sama secara manual: memanggil API, memeriksa `stop_reason`, menjalankan alat, menambahkan hasil, lalu mengulanginya. Tool Runner melakukan ini untuk Anda. Definisikan setiap alat sebagai fungsi, teruskan daftarnya ke `client.beta.messages.tool_runner()` (typescript: `client.beta.messages.toolRunner()`; java: `client.beta().messages().toolRunner()`; php: `$client->beta->messages->toolRunner()`; csharp: `client.Beta.Messages.ToolRunner()`; go: `client.Beta.Messages.NewToolRunner()`), dan ambil pesan akhir setelah loop selesai. Pembungkusan error, pemformatan hasil, dan pengelolaan percakapan ditangani secara internal.
Setiap SDK menyediakan helper yang mengubah fungsi biasa menjadi alat yang dapat dijalankan dan menurunkan skema input dari signature-nya; tab di bawah ini menunjukkan bentuk idiomatis untuk setiap bahasa.
Tool Runner adalah helper di Claude SDK. Permintaan HTTP mentah tidak memiliki padanannya. Untuk tetap menggunakan curl, gunakan loop dari [Cincin 4](https://platform.claude.com/docs/id/agents-and-tools/tool-use/build-a-tool-using-agent#ring-4-error-handling).
Tool Runner adalah helper di Claude SDK. CLI `ant` tidak memiliki padanannya. Untuk tetap menggunakan CLI, gunakan loop dari [Cincin 4](https://platform.claude.com/docs/id/agents-and-tools/tool-use/build-a-tool-using-agent#ring-4-error-handling).
```python Python
# Ring 5: Abstraksi SDK Tool Runner.
import json
import anthropic
from anthropic import beta_tool
client = anthropic.Anthropic()
@beta_tool
def create_calendar_event(
title: str,
start: str,
end: str,
attendees: list[str] | None = None,
recurrence: dict | None = None,
) -> str:
"""Create a calendar event with attendees and optional recurrence.
Args:
title: Event title.
start: Start time in ISO 8601 format.
end: End time in ISO 8601 format.
attendees: Email addresses to invite.
recurrence: Dict with 'frequency' (daily, weekly, monthly) and 'count'.
"""
if attendees and len(attendees) > 10:
raise ValueError("Too many attendees (max 10)")
return json.dumps({"event_id": "evt_123", "status": "created", "title": title})
@beta_tool
def list_calendar_events(date: str) -> str:
"""List all calendar events on a given date.
Args:
date: Date in YYYY-MM-DD format.
"""
return json.dumps(
{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}
)
final_message = client.beta.messages.tool_runner(
model="claude-opus-5-5",
max_tokens=1024,
tools=[create_calendar_event, list_calendar_events],
messages=[
{
"role": "user",
"content": "Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.",
}
],
).until_done()
for block in final_message.content:
if block.type == "text":
print(block.text)
```
```typescript TypeScript
// Ring 5: Abstraksi SDK Tool Runner.
import Anthropic from "@anthropic-ai/sdk";
import { betaZodTool } from "@anthropic-ai/sdk/helpers/beta/zod";
import { z } from "zod";
const client = new Anthropic();
const createCalendarEvent = betaZodTool({
name: "create_calendar_event",
description: "Create a calendar event with attendees and optional recurrence.",
inputSchema: z.object({
title: z.string(),
start: z.string().datetime(),
end: z.string().datetime(),
attendees: z.array(z.string().email()).optional(),
recurrence: z
.object({
frequency: z.enum(["daily", "weekly", "monthly"]),
count: z.number().int().min(1)
})
.optional()
}),
run: async (input) => {
if (input.attendees && input.attendees.length > 10) {
throw new Error("Too many attendees (max 10)");
}
return JSON.stringify({
event_id: "evt_123",
status: "created",
title: input.title
});
}
});
const listCalendarEvents = betaZodTool({
name: "list_calendar_events",
description: "List all calendar events on a given date.",
inputSchema: z.object({
date: z.string().date()
}),
run: async () => {
return JSON.stringify({
events: [{ title: "Existing meeting", start: "14:00", end: "15:00" }]
});
}
});
const finalMessage = await client.beta.messages.toolRunner({
model: "claude-opus-5-5",
max_tokens: 1024,
tools: [createCalendarEvent, listCalendarEvents],
messages: [
{
role: "user",
content:
"Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts."
}
]
});
for (const block of finalMessage.content) {
if (block.type === "text") {
console.log(block.text);
}
}
```
```csharp C#
// Ring 5: Abstraksi SDK Tool Runner.
using System;
using System.Collections.Generic;
using System.Text.Json;
using System.Threading.Tasks;
using Anthropic;
using Anthropic.Helpers.Beta;
using Anthropic.Models.Beta.Messages;
using MessageCreateParams = Anthropic.Models.Beta.Messages.MessageCreateParams;
using InputSchema = Anthropic.Models.Beta.Messages.InputSchema;
using Role = Anthropic.Models.Beta.Messages.Role;
using Model = Anthropic.Models.Messages.Model;
AnthropicClient client = new();
// Definisikan setiap alat sebagai runnable tool: definisinya memuat JSON Schema
// dan callback Run berisi implementasinya. Melempar exception akan mengirim
// pesan kembali ke Claude sebagai hasil alat dengan is_error diatur.
var createCalendarEvent = new BetaRunnableTool
{
Name = "create_calendar_event",
Definition = new BetaTool
{
Name = "create_calendar_event",
Description = "Create a calendar event with attendees and optional recurrence.",
InputSchema = new InputSchema
{
Properties = new Dictionary
{
["title"] = JsonSerializer.SerializeToElement(new { type = "string", description = "Event title" }),
["start"] = JsonSerializer.SerializeToElement(new { type = "string", description = "Start time in ISO 8601 format" }),
["end"] = JsonSerializer.SerializeToElement(new { type = "string", description = "End time in ISO 8601 format" }),
["attendees"] = JsonSerializer.SerializeToElement(new
{
type = "array",
items = new { type = "string" },
description = "Email addresses to invite",
}),
["recurrence"] = JsonSerializer.SerializeToElement(new
{
type = "object",
properties = new
{
frequency = new { @enum = new[] { "daily", "weekly", "monthly" } },
count = new { type = "integer", minimum = 1 },
},
}),
},
Required = ["title", "start", "end"],
},
},
Run = (toolUse, _) =>
{
if (toolUse.Input.TryGetValue("attendees", out var attendees) && attendees.GetArrayLength() > 10)
{
throw new InvalidOperationException("Too many attendees (max 10)");
}
var title = toolUse.Input.TryGetValue("title", out var t) ? t.GetString() : "";
return Task.FromResult(
JsonSerializer.Serialize(new { event_id = "evt_123", status = "created", title })
);
},
};
var listCalendarEvents = new BetaRunnableTool
{
Name = "list_calendar_events",
Definition = new BetaTool
{
Name = "list_calendar_events",
Description = "List all calendar events on a given date.",
InputSchema = new InputSchema
{
Properties = new Dictionary
{
["date"] = JsonSerializer.SerializeToElement(new { type = "string", description = "Date in YYYY-MM-DD format" }),
},
Required = ["date"],
},
},
Run = (toolUse, _) => Task.FromResult(
"""{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}"""
),
};
// Runner memanggil API, menjalankan alat yang diminta, dan mengirim hasilnya kembali
// hingga Claude menghasilkan jawaban akhir.
var runner = client.Beta.Messages.ToolRunner(
new MessageCreateParams
{
Model = Model.ClaudeOpus5_5,
MaxTokens = 1024,
Messages =
[
new()
{
Role = Role.User,
Content = "Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.",
},
],
},
[createCalendarEvent, listCalendarEvents]
);
BetaMessage? finalMessage = null;
await foreach (var message in runner)
{
finalMessage = message;
}
foreach (var block in finalMessage!.Content)
{
if (block.TryPickText(out var text))
{
Console.WriteLine(text.Text);
}
}
```
```go Go
// Ring 5: Abstraksi SDK Tool Runner.
package main
import (
"context"
"fmt"
"log"
"github.com/anthropics/anthropic-sdk-go"
"github.com/anthropics/anthropic-sdk-go/toolrunner"
)
// Struct input mendefinisikan skema setiap alat. Tool runner menghasilkan
// JSON Schema dari field struct beserta tag jsonschema-nya.
type RecurrenceInput struct {
Frequency string `json:"frequency,omitempty" jsonschema:"enum=daily,enum=weekly,enum=monthly,description=How often the event repeats"`
Count int `json:"count,omitempty" jsonschema:"description=Number of occurrences"`
}
type CreateCalendarEventInput struct {
Title string `json:"title" jsonschema:"required,description=Event title"`
Start string `json:"start" jsonschema:"required,description=Start time in ISO 8601 format"`
End string `json:"end" jsonschema:"required,description=End time in ISO 8601 format"`
Attendees []string `json:"attendees,omitempty" jsonschema:"description=Email addresses to invite"`
Recurrence *RecurrenceInput `json:"recurrence,omitempty"`
}
type ListCalendarEventsInput struct {
Date string `json:"date" jsonschema:"required,description=Date in YYYY-MM-DD format"`
}
func main() {
client := anthropic.NewClient()
ctx := context.Background()
// Definisikan setiap alat sebagai fungsi handler. Mengembalikan error akan mengirim
// pesan kembali ke Claude sebagai hasil alat dengan is_error diatur.
createCalendarEvent, err := toolrunner.NewBetaToolFromJSONSchema(
"create_calendar_event",
"Create a calendar event with attendees and optional recurrence.",
func(ctx context.Context, input CreateCalendarEventInput) (anthropic.BetaToolResultBlockParamContentUnion, error) {
if len(input.Attendees) > 10 {
return anthropic.BetaToolResultBlockParamContentUnion{}, fmt.Errorf("too many attendees (max 10)")
}
return anthropic.BetaToolResultBlockParamContentUnion{
OfText: &anthropic.BetaTextBlockParam{
Text: fmt.Sprintf(`{"event_id": "evt_123", "status": "created", "title": %q}`, input.Title),
},
}, nil
},
)
if err != nil {
log.Fatal(err)
}
listCalendarEvents, err := toolrunner.NewBetaToolFromJSONSchema(
"list_calendar_events",
"List all calendar events on a given date.",
func(ctx context.Context, input ListCalendarEventsInput) (anthropic.BetaToolResultBlockParamContentUnion, error) {
return anthropic.BetaToolResultBlockParamContentUnion{
OfText: &anthropic.BetaTextBlockParam{
Text: `{"events": [{"title": "Existing meeting", "start": "14:00", "end": "15:00"}]}`,
},
}, nil
},
)
if err != nil {
log.Fatal(err)
}
// Runner memanggil API, menjalankan alat yang diminta, dan mengirim hasilnya kembali
// hingga Claude menghasilkan jawaban akhir.
runner := client.Beta.Messages.NewToolRunner(
[]anthropic.BetaTool{createCalendarEvent, listCalendarEvents},
anthropic.BetaToolRunnerParams{
BetaMessageNewParams: anthropic.BetaMessageNewParams{
Model: anthropic.ModelClaudeOpus5_5,
MaxTokens: 1024,
Messages: []anthropic.BetaMessageParam{
anthropic.NewBetaUserMessage(anthropic.NewBetaTextBlock(
"Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.",
)),
},
},
},
)
var finalMessage *anthropic.BetaMessage
for message, err := range runner.All(ctx) {
if err != nil {
log.Fatal(err)
}
finalMessage = message
}
for _, block := range finalMessage.Content {
if block.Type == "text" {
fmt.Println(block.Text)
}
}
}
```
```java Java
// Ring 5: Abstraksi SDK Tool Runner.
import com.anthropic.client.AnthropicClient;
import com.anthropic.client.okhttp.AnthropicOkHttpClient;
import com.anthropic.helpers.BetaToolRunner;
import com.anthropic.models.beta.messages.BetaMessage;
import com.anthropic.models.beta.messages.MessageCreateParams;
import com.anthropic.models.messages.Model;
import com.fasterxml.jackson.annotation.JsonClassDescription;
import com.fasterxml.jackson.annotation.JsonPropertyDescription;
import java.util.List;
import java.util.function.Supplier;
// Definisikan setiap alat sebagai kelas: field-nya menjelaskan skema input, dan
// metode get() berisi implementasinya. Melempar exception akan mengirim
// pesan kembali ke Claude sebagai hasil alat dengan is_error diatur.
@JsonClassDescription("Create a calendar event with attendees.")
static class CreateCalendarEvent implements Supplier {
@JsonPropertyDescription("Event title")
public String title;
@JsonPropertyDescription("Start time in ISO 8601 format")
public String start;
@JsonPropertyDescription("End time in ISO 8601 format")
public String end;
@JsonPropertyDescription("Email addresses to invite")
public List attendees;
@Override
public String get() {
if (attendees != null && attendees.size() > 10) {
throw new IllegalArgumentException("Too many attendees (max 10)");
}
return "{\"event_id\": \"evt_123\", \"status\": \"created\", \"title\": \"" + title + "\"}";
}
}
@JsonClassDescription("List all calendar events on a given date.")
static class ListCalendarEvents implements Supplier {
@JsonPropertyDescription("Date in YYYY-MM-DD format")
public String date;
@Override
public String get() {
return "{\"events\": [{\"title\": \"Existing meeting\", \"start\": \"14:00\", \"end\": \"15:00\"}]}";
}
}
void main() {
AnthropicClient client = AnthropicOkHttpClient.fromEnv();
// Runner memanggil API, menjalankan alat yang diminta, dan mengirim hasilnya kembali
// hingga Claude menghasilkan jawaban akhir.
BetaToolRunner runner = client.beta()
.messages()
.toolRunner(MessageCreateParams.builder()
.model(Model.CLAUDE_OPUS_5_5)
.maxTokens(1024)
.addBeta("structured-outputs-2025-11-13")
.addUserMessage("Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.")
.addTool(CreateCalendarEvent.class)
.addTool(ListCalendarEvents.class)
.build());
BetaMessage finalMessage = null;
for (BetaMessage message : runner) {
finalMessage = message;
}
finalMessage.content().stream()
.flatMap(block -> block.text().stream())
.forEach(textBlock -> IO.println(textBlock.text()));
}
```
```php PHP
'create_calendar_event',
'description' => 'Create a calendar event with attendees and optional recurrence.',
'input_schema' => [
'type' => 'object',
'properties' => [
'title' => ['type' => 'string', 'description' => 'Event title'],
'start' => ['type' => 'string', 'description' => 'Start time in ISO 8601 format'],
'end' => ['type' => 'string', 'description' => 'End time in ISO 8601 format'],
'attendees' => [
'type' => 'array',
'items' => ['type' => 'string'],
'description' => 'Email addresses to invite',
],
'recurrence' => [
'type' => 'object',
'properties' => [
'frequency' => ['enum' => ['daily', 'weekly', 'monthly']],
'count' => ['type' => 'integer', 'minimum' => 1],
],
],
],
'required' => ['title', 'start', 'end'],
],
],
run: function (array $input): string {
if (count($input['attendees'] ?? []) > 10) {
throw new \InvalidArgumentException('Too many attendees (max 10)');
}
return json_encode([
'event_id' => 'evt_123',
'status' => 'created',
'title' => $input['title'],
]);
},
);
$listCalendarEvents = new BetaRunnableTool(
definition: [
'name' => 'list_calendar_events',
'description' => 'List all calendar events on a given date.',
'input_schema' => [
'type' => 'object',
'properties' => [
'date' => ['type' => 'string', 'description' => 'Date in YYYY-MM-DD format'],
],
'required' => ['date'],
],
],
run: fn (array $input): string => json_encode([
'events' => [['title' => 'Existing meeting', 'start' => '14:00', 'end' => '15:00']],
]),
);
// Runner memanggil API, menjalankan alat yang diminta, dan mengirim hasilnya kembali
// hingga Claude menghasilkan jawaban akhir.
$runner = $client->beta->messages->toolRunner(
maxTokens: 1024,
messages: [
[
'role' => 'user',
'content' => 'Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts.',
],
],
model: Model::CLAUDE_OPUS_5_5,
tools: [$createCalendarEvent, $listCalendarEvents],
);
$finalMessage = null;
foreach ($runner as $message) {
$finalMessage = $message;
}
foreach ($finalMessage->content as $block) {
if ($block->type === 'text') {
echo $block->text, "\n";
}
}
```
```ruby Ruby
# Ring 5: Abstraksi SDK Tool Runner.
require "anthropic"
client = Anthropic::Client.new
# Definisikan setiap alat sebagai kelas: model input bertipe menjelaskan skema, dan
# metode call berisi implementasinya. Memunculkan error akan mengirim pesannya
# kembali ke Claude sebagai hasil alat dengan is_error diatur.
class RecurrenceInput < Anthropic::BaseModel
optional :frequency, Anthropic::InputSchema::EnumOf["daily", "weekly", "monthly"],
doc: "How often the event repeats"
optional :count, Integer, doc: "Number of occurrences"
end
class CreateCalendarEventInput < Anthropic::BaseModel
required :title, String, doc: "Event title"
required :start, String, doc: "Start time in ISO 8601 format"
required :end, String, doc: "End time in ISO 8601 format"
optional :attendees, Anthropic::InputSchema::ArrayOf[String], doc: "Email addresses to invite"
optional :recurrence, RecurrenceInput, doc: "Optional recurrence rule"
end
class CreateCalendarEvent < Anthropic::BaseTool
doc "Create a calendar event with attendees and optional recurrence."
input_schema CreateCalendarEventInput
def call(input)
raise ArgumentError, "Too many attendees (max 10)" if input.attendees && input.attendees.length > 10
JSON.generate({event_id: "evt_123", status: "created", title: input.title})
end
end
class ListCalendarEventsInput < Anthropic::BaseModel
required :date, String, doc: "Date in YYYY-MM-DD format"
end
class ListCalendarEvents < Anthropic::BaseTool
doc "List all calendar events on a given date."
input_schema ListCalendarEventsInput
def call(input)
JSON.generate({events: [{title: "Existing meeting", start: "14:00", end: "15:00"}]})
end
end
# Runner memanggil API, menjalankan alat yang diminta, dan mengirim hasilnya kembali
# hingga Claude menghasilkan jawaban akhir.
runner = client.beta.messages.tool_runner(
model: "claude-opus-5-5",
max_tokens: 1024,
tools: [CreateCalendarEvent.new, ListCalendarEvents.new],
messages: [
{
role: "user",
content: "Check what I have on Monday, March 30, 2026, then schedule a one-hour planning session that day that avoids any conflicts."
}
]
)
final_message = nil
runner.each_message { |message| final_message = message }
final_message.content.each do |block|
puts block.text if block.type == :text
end
```
**Apa yang diharapkan**
```text Output wrap
I checked your calendar for Monday, March 30 and found an existing meeting from 2pm to 3pm. I've scheduled the planning session for 10am to 11am to avoid the conflict.
```
Outputnya identik dengan Cincin 3. Perbedaannya ada pada kodenya: kira-kira setengah jumlah baris, tanpa loop manual, dan skemanya berada di samping implementasinya.
## Apa yang Anda bangun
Anda memulai dengan satu panggilan alat yang di-hardcode dan mengakhiri dengan agen berbentuk produksi yang menangani banyak alat, panggilan paralel, dan error, lalu meringkas semuanya ke dalam Tool Runner. Sepanjang perjalanan, Anda melihat setiap bagian dari protokol penggunaan alat: blok `tool_use`, blok `tool_result`, pencocokan `tool_use_id`, pemeriksaan `stop_reason`, dan pensinyalan `is_error`.
## Langkah selanjutnya
Spesifikasi skema dan praktik terbaik.
Referensi lengkap abstraksi SDK.
Memperbaiki error penggunaan alat yang umum.