Migrate from OpenRouter

OpenRouter and AnonRouter expose the same developer surface: the OpenAI Chat Completions API, spoken through the official OpenAI Python and TypeScript SDKs. Both use creator/model ids, and many ids are identical on the two catalogs. For most applications the port is exactly two changes: the base URL and the API key.

https://openrouter.ai/api/v1   ->   https://api.anonrouter.ai/v1
sk-or-v1-...                   ->   ar_...

Everything below was verified request-by-request with the official OpenAI SDKs (Python and TypeScript) against an AnonRouter gateway.

Before you begin

1. Create an AnonRouter account and an inference key in the dashboard. Keys are prefixed ar_ and shown once.
2. When you create the key, enable OpenAI-compatible access on it. This is the static-key mode OpenRouter users expect, and it is off by default because the fully private ticket flow is the default. See Compatibility mode for the tradeoff.

The two-line port

from openai import OpenAI

client = OpenAI(
    base_url="https://api.anonrouter.ai/v1",   # was https://openrouter.ai/api/v1
    api_key=os.environ["ANONROUTER_API_KEY"],  # was OPENROUTER_API_KEY
    max_retries=0,                             # see "Disable automatic retries"
)

completion = client.chat.completions.create(
    model="anthropic/claude-sonnet-4.5",       # same id on both catalogs
    max_tokens=256,
    messages=[{"role": "user", "content": "Hello"}],
)

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

Streaming, stream_options: {"include_usage": true}, tool calling with multi-turn tool-result loops, response_format structured outputs, image (image_url) content parts, and models.list() all work through the same two changes.

Model ids

Both routers use creator/model slugs, and the overlap is large: anthropic/claude-sonnet-4.5, openai/gpt-4o, google/gemini-3.5-flash, deepseek/deepseek-v3.2, qwen/..., moonshotai/... resolve on both. The catalogs are not identical, so map your model list once:

curl -s https://api.anonrouter.ai/v1/models \
  -H "Authorization: Bearer $ANONROUTER_API_KEY" | jq -r '.data[].id'

Differences to know:

Each /v1/models entry also carries AnonRouter metadata the OpenAI SDK ignores: privacy_class (anonymous, private, e2ee), per-route capabilities (tools, reasoning efforts, vision), and pricing. Use capabilities the way you used OpenRouter's supported_parameters.

Request fields: what maps where

Verified field by field. "Ignored" means the request succeeds and the field is silently dropped, so you can migrate without stripping it first.

Works unchanged

Accepted and ignored

Must change

Disable automatic retries

Set max_retries=0 (Python) or maxRetries: 0 (TypeScript). AnonRouter does not yet support client-supplied idempotency, so an SDK auto-retry after an ambiguous failure could start a second paid generation. The OpenAI SDK default is 2 retries, so this is worth changing during the port. Handle retries yourself where you need them.

Errors and limits

Errors use the OpenAI envelope, so typed SDK exceptions keep working: AuthenticationError on a bad key, NotFoundError on an unknown model, RateLimitError on 429. Your existing error handling ports as-is.

Two OpenRouter surfaces have no AnonRouter equivalent and fail with 404: the Responses API (client.responses.*) and models.retrieve(id) (use models.list()). Image and speech generation exist as separate Studio routes rather than OpenAI-style endpoints.

What you gain

• A privacy floor instead of a preference. Every route is labeled anonymous, private, or e2ee, and provider.minimum_privacy is enforced with no silent downgrade. See Privacy.
• Routing transparency headers on every completion: x-anonrouter-provider, x-anonrouter-routing, x-anonrouter-provider-attempts, x-anonrouter-provider-fallback, x-anonrouter-privacy-class.
• Inline cost accounting without asking: non-streaming responses carry usage.cost in USD.
• Embeddings through the same SDK and key (POST /v1/embeddings), which OpenRouter does not offer.
• An upgrade path beyond drop-in. When a workload needs unlinkability, switch that call site to the ticket flow or an E2EE model. The request body stays the same, only authentication changes.