# Understudy Gateway API

**Canonical:** https://apis.io/apis/understudy-labs/understudy-gateway-api/  
**Provider:** Understudy Labs — https://apis.io/providers/understudy-labs/  
**Base URL:** https://api.understudylabs.com  
**Documentation:** https://docs.understudylabs.com/reference/proxy-endpoints

Understudy Gateway API is one of 12 APIs that [Understudy Labs](https://apis.io/providers/understudy-labs/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include LLM Gateway, Proxy, and Model Routing. The published artifact set on APIs.io includes API documentation and an API reference.

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.

## Machine-readable artifacts (5)

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

## Other Understudy Labs APIs (11)

- [Understudy Control Plane API](https://apis.io/apis/understudy-labs/understudy-control-plane-api/)
- [Understudy Labs Capabilities API](https://apis.io/apis/understudy-labs/understudy-labs-capabilities-api/)
- [Understudy Labs Conversations API](https://apis.io/apis/understudy-labs/understudy-labs-conversations-api/)
- [Understudy Labs Downloads API](https://apis.io/apis/understudy-labs/understudy-labs-downloads-api/)
- [Understudy Labs Feedback API](https://apis.io/apis/understudy-labs/understudy-labs-feedback-api/)
- [Understudy Labs Metrics API](https://apis.io/apis/understudy-labs/understudy-labs-metrics-api/)
- [Understudy Labs Models API](https://apis.io/apis/understudy-labs/understudy-labs-models-api/)
- [Understudy Labs Residency API](https://apis.io/apis/understudy-labs/understudy-labs-residency-api/)
- [Understudy Labs Runs API](https://apis.io/apis/understudy-labs/understudy-labs-runs-api/)
- [Understudy Labs Status API](https://apis.io/apis/understudy-labs/understudy-labs-status-api/)
- [Understudy Labs Supervision API](https://apis.io/apis/understudy-labs/understudy-labs-supervision-api/)

## Tags

LLM Gateway, Proxy, Model Routing

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/understudy-labs/understudy-gateway-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/understudy-labs/.