openapi: 3.2.0 info: title: LiteLLM [beta] Anthropic `/v1/messages` API description: "Enterprise Edition \n\nProxy Server to call 100+ LLMs in the OpenAI format. [**Customize Swagger Docs**](https://docs.litellm.ai/docs/proxy/enterprise#swagger-docs---custom-routes--branding)\n\n\U0001F449 [```LiteLLM Admin Panel on /ui```](/ui). Create, Edit Keys with SSO. Having issues? Try [```Fallback Login```](/fallback/login)\n\n\U0001F4B8 [```LiteLLM Model Cost Map```](https://models.litellm.ai/).\n\n\U0001F50E [```LiteLLM Model Hub```](/ui/model_hub_table). See available models on the proxy. [**Docs**](https://docs.litellm.ai/docs/proxy/ai_hub)" version: 1.95.0 x-operator: institution x-provenance: method: probed source: https://llmproxy.uva.nl/openapi.json retrieved: '2026-08-19' note: Document is generated by the LiteLLM proxy software the University of Amsterdam self-hosts; the deployment, the key issuance and the host (llmproxy.uva.nl, UvA Azure) are the institution's. servers[] added by API Evangelist because the served document omits it; nothing else altered. servers: - url: https://llmproxy.uva.nl description: University of Amsterdam / Amsterdam University of Applied Sciences shared AI gateway tags: - name: '[beta] Anthropic `/v1/messages`' paths: /v1/messages: post: tags: - '[beta] Anthropic `/v1/messages`' summary: Anthropic Response description: 'Use `{PROXY_BASE_URL}/anthropic/v1/messages` instead - [Docs](https://docs.litellm.ai/docs/pass_through/anthropic_completion). This was a BETA endpoint that calls 100+ LLMs in the anthropic format.' operationId: anthropic_response_v1_messages_post responses: '200': description: Successful Response content: application/json: schema: {} security: - APIKeyHeader: [] components: securitySchemes: APIKeyHeader: type: apiKey description: Bearer token in: header name: x-litellm-api-key