Anthropic Adapter | TanStack AI Docs

The Anthropic adapter provides access to Claude models, including Claude 3.5 Sonnet, Claude 3 Opus, and more.

Installation

bash

npm install @tanstack/ai-anthropic

npm install @tanstack/ai-anthropic

Basic Usage

typescript

import { chat } from "@tanstack/ai";
import { anthropic } from "@tanstack/ai-anthropic";

const adapter = anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY!,
});

const stream = chat({
  adapter,
  messages: [{ role: "user", content: "Hello!" }],
  model: "claude-3-5-sonnet-20241022",
});

import { chat } from "@tanstack/ai";
import { anthropic } from "@tanstack/ai-anthropic";

const adapter = anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY!,
});

const stream = chat({
  adapter,
  messages: [{ role: "user", content: "Hello!" }],
  model: "claude-3-5-sonnet-20241022",
});

Configuration

typescript

import { anthropic, type AnthropicConfig } from "@tanstack/ai-anthropic";

const config: AnthropicConfig = {
  apiKey: process.env.ANTHROPIC_API_KEY!,
};

const adapter = anthropic(config);

import { anthropic, type AnthropicConfig } from "@tanstack/ai-anthropic";

const config: AnthropicConfig = {
  apiKey: process.env.ANTHROPIC_API_KEY!,
};

const adapter = anthropic(config);

Available Models

Chat Models

claude-3-5-sonnet-20241022 - Latest Claude 3.5 Sonnet
claude-3-5-sonnet-20240620 - Claude 3.5 Sonnet
claude-3-opus-20240229 - Claude 3 Opus
claude-3-sonnet-20240229 - Claude 3 Sonnet
claude-3-haiku-20240307 - Claude 3 Haiku
claude-2.1 - Claude 2.1
claude-2.0 - Claude 2.0

Example: Chat Completion

typescript

import { chat, toStreamResponse } from "@tanstack/ai";
import { anthropic } from "@tanstack/ai-anthropic";

const adapter = anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY!,
});

export async function POST(request: Request) {
  const { messages } = await request.json();

  const stream = chat({
    adapter,
    messages,
    model: "claude-3-5-sonnet-20241022",
  });

  return toStreamResponse(stream);
}

import { chat, toStreamResponse } from "@tanstack/ai";
import { anthropic } from "@tanstack/ai-anthropic";

const adapter = anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY!,
});

export async function POST(request: Request) {
  const { messages } = await request.json();

  const stream = chat({
    adapter,
    messages,
    model: "claude-3-5-sonnet-20241022",
  });

  return toStreamResponse(stream);
}

Example: With Tools

typescript

import { chat, toolDefinition } from "@tanstack/ai";
import { anthropic } from "@tanstack/ai-anthropic";
import { z } from "zod";

const adapter = anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY!,
});

const searchDatabaseDef = toolDefinition({
  name: "search_database",
  description: "Search the database",
  inputSchema: z.object({
    query: z.string(),
  }),
});

const searchDatabase = searchDatabaseDef.server(async ({ query }) => {
  // Search database
  return { results: [...] };
});

const stream = chat({
  adapter,
  messages,
  model: "claude-3-5-sonnet-20241022",
  tools: [searchDatabase],
});

import { chat, toolDefinition } from "@tanstack/ai";
import { anthropic } from "@tanstack/ai-anthropic";
import { z } from "zod";

const adapter = anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY!,
});

const searchDatabaseDef = toolDefinition({
  name: "search_database",
  description: "Search the database",
  inputSchema: z.object({
    query: z.string(),
  }),
});

const searchDatabase = searchDatabaseDef.server(async ({ query }) => {
  // Search database
  return { results: [...] };
});

const stream = chat({
  adapter,
  messages,
  model: "claude-3-5-sonnet-20241022",
  tools: [searchDatabase],
});

Provider Options

Anthropic supports provider-specific options:

typescript

const stream = chat({
  adapter: anthropic({ apiKey: process.env.ANTHROPIC_API_KEY! }),
  messages,
  model: "claude-3-5-sonnet-20241022",
  providerOptions: {
    thinking: {
      type: "enabled",
      budgetTokens: 1000,
    },
    cacheControl: {
      type: "ephemeral",
      ttl: "5m",
    },
    sendReasoning: true,
  },
});

const stream = chat({
  adapter: anthropic({ apiKey: process.env.ANTHROPIC_API_KEY! }),
  messages,
  model: "claude-3-5-sonnet-20241022",
  providerOptions: {
    thinking: {
      type: "enabled",
      budgetTokens: 1000,
    },
    cacheControl: {
      type: "ephemeral",
      ttl: "5m",
    },
    sendReasoning: true,
  },
});

Thinking (Extended Thinking)

Enable extended thinking with a token budget. This allows Claude to show its reasoning process, which is streamed as thinking chunks and displayed as ThinkingPart in messages:

typescript

providerOptions: {
  thinking: {
    type: "enabled",
    budget_tokens: 2048, // Maximum tokens for thinking
  },
}

providerOptions: {
  thinking: {
    type: "enabled",
    budget_tokens: 2048, // Maximum tokens for thinking
  },
}

Note: max_tokens must be greater than budget_tokens. The adapter automatically adjusts max_tokens if needed.

Supported Models:

claude-sonnet-4-5-20250929 and newer
claude-opus-4-5-20251101 and newer

When thinking is enabled, the model's reasoning process is streamed separately from the response text and appears as a collapsible thinking section in the UI.

Prompt Caching

Cache prompts for better performance:

typescript

providerOptions: {
  cacheControl: {
    type: "ephemeral",
    ttl: "5m", // Cache TTL: '5m' or '1h'
  },
}

providerOptions: {
  cacheControl: {
    type: "ephemeral",
    ttl: "5m", // Cache TTL: '5m' or '1h'
  },
}

Environment Variables

Set your API key in environment variables:

bash

ANTHROPIC_API_KEY=sk-ant-...

ANTHROPIC_API_KEY=sk-ant-...

API Reference

anthropic(config)

Creates an Anthropic adapter instance.

Parameters:

config.apiKey - Anthropic API key (required)

Returns: An Anthropic adapter instance.

Next Steps

Getting Started - Learn the basics
Tools Guide - Learn about tools
Other Adapters - Explore other providers