LangSmith gateway API

openapi: 3.1.0
info:
  title: LangSmith access_policies gateway API
  description: 'The LangSmith API is used to programmatically create and manage LangSmith resources.


    ## Host

    https://api.smith.langchain.com


    ## Authentication

    To authenticate with the LangSmith API, set the `X-Api-Key` header

    to a valid [LangSmith API key](https://docs.langchain.com/langsmith/create-account-api-key#create-an-api-key).


    '
  version: 0.1.0
servers:
- url: /
tags:
- name: gateway
paths:
  /anthropic/v1/messages:
    post:
      security:
      - API Key: []
      - Tenant ID: []
      - Bearer Auth: []
      description: 'Forwards an Anthropic Messages API request to api.anthropic.com.

        The gateway injects the workspace''s stored ANTHROPIC_API_KEY

        unless the request carries a Claude-Code-style OAuth bearer

        (`Authorization: Bearer sk-ant-oat01-...`), in which case the

        bearer is forwarded as-is and the workspace key is not used.

        Spend-cap and guard policies apply in both modes.


        Streaming (`stream: true`) responses are forwarded as

        `text/event-stream` chunks. Non-streaming responses are

        forwarded as `application/json`.'
      tags:
      - gateway
      summary: Proxy Anthropic Messages through the LLM Gateway
      parameters: []
      responses:
        '200':
          description: Anthropic Messages response, forwarded verbatim
          content:
            application/json:
              schema:
                type: object
        '400':
          description: request body invalid or workspace ANTHROPIC_API_KEY missing
          content:
            application/json:
              schema:
                type: string
        '401':
          description: missing or invalid LangSmith credentials
          content:
            application/json:
              schema:
                type: string
        '402':
          description: request blocked by a spend-cap policy
          content:
            application/json:
              schema:
                type: string
        '403':
          description: Anthropic OAuth passthrough disabled for this organization
          content:
            application/json:
              schema:
                type: string
        '500':
          description: gateway-side failure (secrets load, body prep)
          content:
            application/json:
              schema:
                type: string
        '502':
          description: upstream Anthropic transport failed
          content:
            application/json:
              schema:
                type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
  /gemini/v1beta/models/{model}:
    post:
      security:
      - API Key: []
      - Tenant ID: []
      - Bearer Auth: []
      description: 'Forwards a Gemini v1beta `generateContent` or

        `streamGenerateContent` request to

        generativelanguage.googleapis.com. The gateway injects the

        workspace''s stored GOOGLE_API_KEY as the `x-goog-api-key`

        header; any client-supplied `?key=` query parameter is

        stripped before forwarding so the workspace credential is the

        only one in play. Spend-cap and guard policies apply.


        `streamGenerateContent` responses are forwarded as

        `text/event-stream`; `generateContent` responses are

        forwarded as `application/json`.'
      tags:
      - gateway
      summary: Proxy Google Gemini generateContent through the LLM Gateway
      parameters:
      - description: Model + action, e.g. `gemini-2.0-flash:generateContent` or `gemini-2.0-flash:streamGenerateContent`
        name: model
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Gemini response, forwarded verbatim
          content:
            application/json:
              schema:
                type: object
        '400':
          description: missing model in path or invalid request body
          content:
            application/json:
              schema:
                type: string
        '401':
          description: missing or invalid LangSmith credentials
          content:
            application/json:
              schema:
                type: string
        '402':
          description: request blocked by a spend-cap policy
          content:
            application/json:
              schema:
                type: string
        '500':
          description: gateway-side failure (secrets load, body prep)
          content:
            application/json:
              schema:
                type: string
        '501':
          description: Gemini action not supported by this gateway version
          content:
            application/json:
              schema:
                type: string
        '502':
          description: upstream Gemini transport failed
          content:
            application/json:
              schema:
                type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
  /openai/v1/chat/completions:
    post:
      security:
      - API Key: []
      - Tenant ID: []
      - Bearer Auth: []
      description: 'Forwards an OpenAI Chat Completions request to api.openai.com.

        The request body is the unmodified OpenAI request shape; the

        gateway injects the workspace''s stored OPENAI_API_KEY, applies

        spend-cap and guard policies, and emits a LangSmith trace span

        for the call.


        Streaming (`stream: true`) responses are forwarded as

        `text/event-stream` chunks. Non-streaming responses are

        forwarded as `application/json`.'
      tags:
      - gateway
      summary: Proxy OpenAI Chat Completions through the LLM Gateway
      parameters: []
      responses:
        '200':
          description: OpenAI Chat Completions response, forwarded verbatim
          content:
            application/json:
              schema:
                type: object
        '400':
          description: request body invalid or missing required fields
          content:
            application/json:
              schema:
                type: string
        '401':
          description: missing or invalid LangSmith credentials
          content:
            application/json:
              schema:
                type: string
        '402':
          description: request blocked by a spend-cap policy
          content:
            application/json:
              schema:
                type: string
        '500':
          description: gateway-side failure (secrets load, body prep)
          content:
            application/json:
              schema:
                type: string
        '502':
          description: upstream OpenAI transport failed
          content:
            application/json:
              schema:
                type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
  /openai/v1/responses:
    post:
      security:
      - API Key: []
      - Tenant ID: []
      - Bearer Auth: []
      description: 'Forwards an OpenAI Responses API request to api.openai.com.

        Same auth, policy, and tracing semantics as Chat Completions —

        the workspace''s OPENAI_API_KEY is injected by the gateway and

        the request body is forwarded verbatim.'
      tags:
      - gateway
      summary: Proxy OpenAI Responses through the LLM Gateway
      parameters: []
      responses:
        '200':
          description: OpenAI Responses response, forwarded verbatim
          content:
            application/json:
              schema:
                type: object
        '400':
          description: request body invalid or missing required fields
          content:
            application/json:
              schema:
                type: string
        '401':
          description: missing or invalid LangSmith credentials
          content:
            application/json:
              schema:
                type: string
        '402':
          description: request blocked by a spend-cap policy
          content:
            application/json:
              schema:
                type: string
        '500':
          description: gateway-side failure (secrets load, body prep)
          content:
            application/json:
              schema:
                type: string
        '502':
          description: upstream OpenAI transport failed
          content:
            application/json:
              schema:
                type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
components:
  securitySchemes:
    API Key:
      type: apiKey
      in: header
      name: X-API-Key
    Tenant ID:
      type: apiKey
      in: header
      name: X-Tenant-Id
    Bearer Auth:
      type: http
      description: Bearer tokens are used to authenticate from the UI. Must also specify x-tenant-id or x-organization-id (for org scoped apis).
      scheme: bearer
    Organization ID:
      type: apiKey
      in: header
      name: X-Organization-Id