Get started

Merge Gateway puts every LLM behind a single API, with intelligent routing, cost management, and security built in. Route to OpenAI, Anthropic, Google, and AWS Bedrock through a single endpoint, with automatic failover and observability.

Merge Gateway SDK

$
pip install merge-gateway-python

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from merge_gateway import MergeGateway
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client = MergeGateway(api_key="YOUR_API_KEY")
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response = client.responses.create(
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    model="openai/gpt-5.2",
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    input=[
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        {"type": "message", "role": "system", "content": "You are a helpful programming tutor. Explain the concepts clearly with practical examples."},
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        {"type": "message", "role": "user", "content": "Explain the concept of recursion in programming with a simple set of examples."},
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    ],
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)
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print(response.output[0].content[0].text)

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response = client.responses.create(
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    model="anthropic/claude-sonnet-5",
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    input=[
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        {"type": "message", "role": "system", "content": "You are a helpful programming tutor. Explain the concepts clearly with practical examples."},
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        {"type": "message", "role": "user", "content": "Explain the concept of recursion in programming with a simple set of examples."},
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    ],
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)

OpenAI SDK

Already using the OpenAI SDK? Point it at Merge Gateway to get multi-provider routing without changing your application code.

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from openai import OpenAI
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client = OpenAI(
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    api_key="YOUR_API_KEY",
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    base_url="https://api-gateway.merge.dev/v1/openai",
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)

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response = client.chat.completions.create(
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    model="gpt-5.2",
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    messages=[
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        {"role": "system", "content": "You are a helpful programming tutor. Explain the concepts clearly with practical examples."},
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        {"role": "user", "content": "Explain the concept of recursion in programming with a simple set of examples."},
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    ],
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)
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print(response.choices[0].message.content)

AI SDK (Vercel)

Using the Vercel AI SDK? Use the Merge Gateway provider for full access to routing, tags, and cost tracking, or use the quick-start URL shim for zero-install setup.

Recommended: Merge Gateway provider

$
npm install merge-gateway-ai-sdk-provider ai

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import { createMergeGateway } from "merge-gateway-ai-sdk-provider";
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const gateway = createMergeGateway({
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  apiKey: "YOUR_API_KEY",
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});

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import { generateText } from "ai";
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const { text } = await generateText({
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  model: gateway("openai/gpt-5.5"),
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  prompt: "Explain the concept of recursion in programming with a simple set of examples.",
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});
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console.log(text);

The native provider gives you typed access to Gateway features like tags, vendor routing, routing metadata, and structured-output strict control via providerOptions.mergeGateway. generateObject and streamObject map to Gateway’s native json_schema structured output — see Structured outputs.

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import { createMergeGateway } from "merge-gateway-ai-sdk-provider/v5";

Alternative: URL shim (no extra install)

If you already have @ai-sdk/openai installed, point it at Gateway with a base URL change:

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import { createOpenAI } from "@ai-sdk/openai";
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const gateway = createOpenAI({
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  apiKey: "YOUR_API_KEY",
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  baseURL: "https://api-gateway.merge.dev/v1/ai-sdk",
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});
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// All generateText/streamText calls work unchanged

Other SDKs

Gateway is compatible with any SDK that lets you set a custom base URL.

Where two base URLs are listed, both accept the same requests. The second is each SDK’s default base URL shape: the OpenAI SDK appends chat/completions to a /v1 base URL, and the Anthropic SDK appends /v1/messages to the host, so the only change from the vendor’s own base URL is the host. Two exceptions: the OpenAI SDK’s client.responses.* at the /v1 base URL reaches /v1/responses, which is Gateway’s native Responses API rather than OpenAI’s, so use the /v1/openai base URL when you call the Responses API; and the Anthropic SDK’s models.list() at the bare host returns Gateway’s native model listing, so use the /v1/anthropic base URL if you need Anthropic-shaped model listings.

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from anthropic import Anthropic
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client = Anthropic(
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    api_key="YOUR_API_KEY",
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    base_url="https://api-gateway.merge.dev/v1/anthropic",
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)
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message = client.messages.create(
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    model="anthropic/claude-sonnet-5",
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    max_tokens=1024,
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    messages=[
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        {"role": "user", "content": "Explain the concept of recursion in programming with a simple set of examples."},
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    ],
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)
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print(message.content[0].text)

Next steps