OpenPaths is an open source model router and AI gateway. One API key and one base URL (https://openpaths.io/v1) reach language, image, video, speech, music, embedding and 3D models from many providers.

Is OpenPaths compatible with the OpenAI and Anthropic SDKs?

Yes. POST /v1/chat/completions follows the OpenAI schema and POST /v1/messages follows the Anthropic schema. Change the base URL and keep your existing code.

How does OpenPaths pricing work?

Pay as you go at the provider price with near-zero markup. Requests on your own provider keys (BYOK) are recorded at $0. See https://openpaths.io/pricing.

What does openpaths/auto do?

openpaths/auto routes each request to a suitable model automatically, with automatic fallbacks when a provider fails or rate-limits.

Is there an OpenAPI spec or MCP server?

Yes. The OpenAPI 3.1 spec is at https://openpaths.io/openapi.json, the MCP endpoint is https://openpaths.io/mcp, and llms.txt plus llms-full.txt list every model id.

How much does Claude Sonnet 5.5 cost per million tokens?

Claude Sonnet 5.5 costs $2.00 in / $10.00 out per 1M tokens.

Is there a discount for cached tokens on Claude Sonnet 5.5?

No cached-input rate is configured for Claude Sonnet 5.5, so every input token bills at the standard rate.

What does a typical chatbot cost on Claude Sonnet 5.5?

A chatbot sending 300,000 requests per month (1,500 input and 400 output tokens each, 50% cached) costs about $2100.00 per month on Claude Sonnet 5.5.

What is the context window of Claude Sonnet 5.5?

Claude Sonnet 5.5 supports 1M tokens of context and up to 128K output tokens.

What is a cheaper alternative to Claude Sonnet 5.5?

AionLabs: Aion 3.5 is cheaper at $3.17 in / $6.33 out per 1M tokens.

Claude Sonnet 5.5 API Pricing (2026): $2.00 in / $10.00 out per 1M tokens

Claude Sonnet 5.5 pricing: $2.00 in / $10.00 out per 1M tokens. Tier-aware calculator, cheaper alternatives and Artificial Analysis benchmarks.