Understudy Labs

Understudy Gateway API

Anthropic- and OpenAI-compatible LLM proxy at api.understudylabs.com. POST /v1/messages (Anthropic Messages), POST /v1/chat/completions (OpenAI Chat Completions), POST /v1/messages/count_tokens, GET /v1/models (public managed-model catalog), and GET /healthz. Supports bring-your-own-key passthrough and managed catalog models, capture of request/response evidence, canary routing with fallback, and x-understudy-* scoping, tagging, and legibility headers.

GitHub

Documentation

📖
Documentation
https://docs.understudylabs.com/reference/proxy-endpoints
📖
APIReference
https://docs.understudylabs.com/reference/request-headers

Other Resources

🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/understudy-labs/refs/heads/main/apis.yml
🔗
Arazzo
https://raw.githubusercontent.com/api-evangelist/understudy-labs/refs/heads/main/arazzo/_index.yml
🔗
Arazzo
https://raw.githubusercontent.com/api-evangelist/understudy-labs/refs/heads/main/arazzo/understudy-labs-download-warm-and-chat.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: understudy-labs:understudy-gateway-api
name: Understudy Gateway API
description: Anthropic- and OpenAI-compatible LLM proxy at api.understudylabs.com. POST /v1/messages (Anthropic
  Messages), POST /v1/chat/completions (OpenAI Chat Completions), POST /v1/messages/count_tokens, GET
  /v1/models (public managed-model catalog), and GET /healthz. Supports bring-your-own-key passthrough
  and managed catalog models, capture of request/response evidence, canary routing with fallback, and
  x-understudy-* scoping, tagging, and legibility headers.
humanURL: https://docs.understudylabs.com/reference/proxy-endpoints
baseURL: https://api.understudylabs.com
tags:
- LLM Gateway
- Proxy
- Model Routing
properties:
- type: Documentation
  url: https://docs.understudylabs.com/reference/proxy-endpoints
- type: APIReference
  url: https://docs.understudylabs.com/reference/request-headers