Client SDKs | OpenRouter

The Client SDKs give you a thin, type-safe layer over the OpenRouter REST API. It handles authentication, request validation, and response typing so you can call any of 400+ models with a single function call, with no boilerplate and no provider-specific quirks.

Installation

Language	Package
TypeScript	`@openrouter/sdk`
Python	`openrouter`
Go	`go-sdk`

npm install @openrouter/sdk

pnpm add @openrouter/sdk

yarn add @openrouter/sdk

bun add @openrouter/sdk

deno add npm:@openrouter/sdk

pip install openrouter

go get github.com/OpenRouterTeam/go-sdk

All three SDKs are auto-generated from the OpenRouter OpenAPI spec, so new models, parameters, and endpoints appear immediately after each API release.

When to use the Client SDKs

Choose the Client SDKs when you need direct, efficient access to model inference and want to manage your own application logic:

Single-turn completions, send a prompt, get a response
Streaming responses, real-time token-by-token output
Embeddings, video, and rerank, generate vector representations, create videos, and rerank results
API key and credit management, programmatic control over your account
Custom orchestration, you handle conversation loops, tool dispatch, and state yourself

The Client SDKs are intentionally lean. It mirrors the OpenRouter API surface 1:1 with full type safety, so there is no abstraction to fight when you need fine-grained control.

If you want higher-level primitives for building agents (multi-turn loops, tool definitions, stop conditions, and conversation state management), see the Agent SDK instead.

Quick example

import { OpenRouter } from '@openrouter/sdk';

const client = new OpenRouter({
  apiKey: process.env.OPENROUTER_API_KEY,
});

const response = await client.chat.send({
  model: 'openai/gpt-5.2',
  messages: [
    { role: 'user', content: 'Explain quantum computing in one sentence.' },
  ],
});

console.log(response.choices[0].message.content);

from openrouter import OpenRouter
import os

with OpenRouter(api_key=os.getenv("OPENROUTER_API_KEY")) as client:
    response = client.chat.send(
        model="openai/gpt-5.2",
        messages=[
            {"role": "user", "content": "Explain quantum computing in one sentence."}
        ],
    )

    print(response.choices[0].message.content)

Client SDKs vs Agent SDK

	Client SDKs	Agent SDK
Focus	Lean API client, mirrors the REST API with full type safety	Agentic primitives, multi-turn loops, tools, stop conditions
Use when	You want direct model calls and manage orchestration yourself	You want built-in agent loops, tool execution, and state management
Conversation state	You manage it	Managed for you via `callModel`
Tool execution	You dispatch tool calls	Automatic with the `tool()` helper
Languages	TypeScript, Python, Go	TypeScript

Next steps

TypeScript SDK reference
Python SDK reference
Go SDK reference
Agent SDK overview, for building agents with multi-turn loops and tools

​Installation

​When to use the Client SDKs

​Quick example

​Client SDKs vs Agent SDK

​Next steps

Installation

When to use the Client SDKs

Quick example

Client SDKs vs Agent SDK

Next steps