Langbase Agent API

openapi: 3.0.3
info:
  title: Langbase API
  description: >-
    Representative OpenAPI description of the Langbase serverless AI developer
    platform. All endpoints are served from https://api.langbase.com and
    authenticated with a Bearer API key. Generative endpoints (Pipes run,
    Agent run) return Server-Sent Events (SSE) when `stream` is true. This
    document is a faithful representative model authored by API Evangelist and
    is not the provider's official specification.
  termsOfService: https://langbase.com/terms
  contact:
    name: Langbase Support
    url: https://langbase.com/support
  version: '1.0'
servers:
  - url: https://api.langbase.com
    description: Langbase production API
security:
  - api_key: []
tags:
  - name: Pipes
  - name: Agent
  - name: Memory
  - name: Threads
  - name: Tools
  - name: Parser
  - name: Chunker
  - name: Embed
paths:
  /v1/pipes/run:
    post:
      operationId: runPipe
      tags:
        - Pipes
      summary: Run a Pipe.
      description: >-
        Executes a Pipe (deployable AI agent) over a message array. When
        `stream` is true the response is delivered as Server-Sent Events (SSE)
        with incremental delta content. The response includes an `lb-thread-id`
        header for continuing multi-turn conversations.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RunPipeRequest'
      responses:
        '200':
          description: A Pipe run completion, or an SSE stream when stream is true.
          headers:
            lb-thread-id:
              schema:
                type: string
              description: Identifier of the conversation thread.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/RunResponse'
            text/event-stream:
              schema:
                type: string
                description: Server-Sent Events stream of completion chunks.
  /v1/pipes:
    get:
      operationId: listPipes
      tags:
        - Pipes
      summary: List Pipes.
      responses:
        '200':
          description: A list of Pipes.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Pipe'
    post:
      operationId: createPipe
      tags:
        - Pipes
      summary: Create a Pipe.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreatePipeRequest'
      responses:
        '200':
          description: The created Pipe.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Pipe'
  /v1/pipes/{name}:
    post:
      operationId: updatePipe
      tags:
        - Pipes
      summary: Update a Pipe.
      parameters:
        - in: path
          name: name
          required: true
          schema:
            type: string
          description: The name of the Pipe to update.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreatePipeRequest'
      responses:
        '200':
          description: The updated Pipe.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Pipe'
  /v1/agent/run:
    post:
      operationId: runAgent
      tags:
        - Agent
      summary: Run an agent against any of 100+ LLMs.
      description: >-
        Runs a prompt against a model specified as `provider:model_id`
        (for example `openai:gpt-4o-mini`). Supports tools, generation
        controls, and SSE streaming when `stream` is true. A bring-your-own
        LLM provider key may be supplied via the `LB-LLM-Key` header.
      parameters:
        - in: header
          name: LB-LLM-Key
          required: false
          schema:
            type: string
          description: Optional LLM provider API key for bring-your-own-key runs.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RunAgentRequest'
      responses:
        '200':
          description: An agent run response, or an SSE stream when stream is true.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/RunResponse'
            text/event-stream:
              schema:
                type: string
                description: Server-Sent Events stream of completion chunks.
  /v1/memory:
    get:
      operationId: listMemories
      tags:
        - Memory
      summary: List memory stores.
      responses:
        '200':
          description: A list of memory stores.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Memory'
    post:
      operationId: createMemory
      tags:
        - Memory
      summary: Create a memory store.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateMemoryRequest'
      responses:
        '200':
          description: The created memory store.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Memory'
  /v1/memory/{name}:
    delete:
      operationId: deleteMemory
      tags:
        - Memory
      summary: Delete a memory store.
      parameters:
        - in: path
          name: name
          required: true
          schema:
            type: string
      responses:
        '200':
          description: A delete confirmation.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DeleteResponse'
  /v1/memory/retrieve:
    post:
      operationId: retrieveMemory
      tags:
        - Memory
      summary: Retrieve similar chunks (RAG).
      description: >-
        Runs a semantic similarity search over one or more memory stores and
        returns the most relevant chunks, controlled by `topK` (default 20,
        max 100) and optional metadata filters.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RetrieveMemoryRequest'
      responses:
        '200':
          description: An array of retrieved chunks with similarity scores.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/RetrievedChunk'
  /v1/memory/{name}/documents:
    get:
      operationId: listDocuments
      tags:
        - Memory
      summary: List documents in a memory store.
      parameters:
        - in: path
          name: name
          required: true
          schema:
            type: string
      responses:
        '200':
          description: A list of documents.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Document'
    post:
      operationId: uploadDocument
      tags:
        - Memory
      summary: Upload a document to a memory store.
      parameters:
        - in: path
          name: name
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                documentName:
                  type: string
                document:
                  type: string
                  format: binary
              required:
                - documentName
                - document
      responses:
        '200':
          description: The uploaded document.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Document'
  /v1/memory/{name}/documents/{documentName}:
    delete:
      operationId: deleteDocument
      tags:
        - Memory
      summary: Delete a document from a memory store.
      parameters:
        - in: path
          name: name
          required: true
          schema:
            type: string
        - in: path
          name: documentName
          required: true
          schema:
            type: string
      responses:
        '200':
          description: A delete confirmation.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DeleteResponse'
  /v1/threads:
    post:
      operationId: createThread
      tags:
        - Threads
      summary: Create a conversation thread.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateThreadRequest'
      responses:
        '200':
          description: The created thread.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Thread'
  /v1/threads/{threadId}:
    get:
      operationId: getThread
      tags:
        - Threads
      summary: Get a thread.
      parameters:
        - in: path
          name: threadId
          required: true
          schema:
            type: string
      responses:
        '200':
          description: A thread object.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Thread'
    patch:
      operationId: updateThread
      tags:
        - Threads
      summary: Update a thread.
      parameters:
        - in: path
          name: threadId
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                metadata:
                  type: object
                  additionalProperties:
                    type: string
      responses:
        '200':
          description: The updated thread.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Thread'
    delete:
      operationId: deleteThread
      tags:
        - Threads
      summary: Delete a thread.
      parameters:
        - in: path
          name: threadId
          required: true
          schema:
            type: string
      responses:
        '200':
          description: A delete confirmation.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DeleteResponse'
  /v1/threads/{threadId}/messages:
    get:
      operationId: listMessages
      tags:
        - Threads
      summary: List messages in a thread.
      parameters:
        - in: path
          name: threadId
          required: true
          schema:
            type: string
      responses:
        '200':
          description: A list of messages.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Message'
    post:
      operationId: appendMessages
      tags:
        - Threads
      summary: Append messages to a thread.
      parameters:
        - in: path
          name: threadId
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: array
              items:
                $ref: '#/components/schemas/Message'
      responses:
        '200':
          description: The appended messages.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Message'
  /v1/tools/web-search:
    post:
      operationId: webSearch
      tags:
        - Tools
      summary: Run a live web search.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/WebSearchRequest'
      responses:
        '200':
          description: An array of search results.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/WebSearchResult'
  /v1/tools/crawl:
    post:
      operationId: crawl
      tags:
        - Tools
      summary: Crawl and extract content from web pages.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CrawlRequest'
      responses:
        '200':
          description: An array of crawled page contents.
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/WebSearchResult'
  /v1/parser:
    post:
      operationId: parseDocument
      tags:
        - Parser
      summary: Parse a document into clean text.
      description: >-
        Extracts clean text from an uploaded document. Supports PDF, CSV,
        XLSX, XLS and more, up to 10 MB.
      requestBody:
        required: true
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                document:
                  type: string
                  format: binary
                documentName:
                  type: string
                contentType:
                  type: string
              required:
                - document
                - documentName
                - contentType
      responses:
        '200':
          description: The parsed document content.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ParseResponse'
  /v1/chunker:
    post:
      operationId: chunkContent
      tags:
        - Chunker
      summary: Split text into overlapping chunks.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ChunkRequest'
      responses:
        '200':
          description: An array of text chunks.
          content:
            application/json:
              schema:
                type: array
                items:
                  type: string
  /v1/embed:
    post:
      operationId: embed
      tags:
        - Embed
      summary: Generate embedding vectors.
      description: >-
        Generates embedding vectors for up to 100 chunks per request, each up
        to 8192 characters, using OpenAI, Cohere, or Google embedding models.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EmbedRequest'
      responses:
        '200':
          description: A two-dimensional array of embedding vectors.
          content:
            application/json:
              schema:
                type: array
                items:
                  type: array
                  items:
                    type: number
                    format: float
components:
  securitySchemes:
    api_key:
      type: http
      scheme: bearer
      bearerFormat: apiKey
  schemas:
    Message:
      type: object
      properties:
        role:
          type: string
          enum:
            - system
            - user
            - assistant
            - tool
        content:
          type: string
        name:
          type: string
      required:
        - role
    RunPipeRequest:
      type: object
      properties:
        messages:
          type: array
          items:
            $ref: '#/components/schemas/Message'
        variables:
          type: object
          additionalProperties:
            type: string
          description: Dynamic variables for adaptable prompts.
        threadId:
          type: string
          description: Continue an existing conversation thread.
        stream:
          type: boolean
          default: false
          description: When true, responses are streamed as Server-Sent Events.
        tools:
          type: array
          items:
            type: object
        memory:
          type: array
          items:
            type: object
          description: Memory objects to override the Pipe defaults.
      required:
        - messages
    RunAgentRequest:
      type: object
      properties:
        model:
          type: string
          description: Model as provider:model_id, e.g. openai:gpt-4o-mini.
          example: openai:gpt-4o-mini
        input:
          oneOf:
            - type: string
            - type: array
              items:
                $ref: '#/components/schemas/Message'
        instructions:
          type: string
        stream:
          type: boolean
          default: false
        tools:
          type: array
          items:
            type: object
        temperature:
          type: number
        top_p:
          type: number
        max_tokens:
          type: integer
      required:
        - model
        - input
    RunResponse:
      type: object
      properties:
        completion:
          type: string
          description: The generated text completion.
        raw:
          type: object
          description: The raw upstream provider response.
        usage:
          $ref: '#/components/schemas/Usage'
    Usage:
      type: object
      properties:
        prompt_tokens:
          type: integer
        completion_tokens:
          type: integer
        total_tokens:
          type: integer
    Pipe:
      type: object
      properties:
        name:
          type: string
        description:
          type: string
        status:
          type: string
          enum:
            - public
            - private
        model:
          type: string
        apiKey:
          type: string
          description: The run key scoped to this Pipe.
    CreatePipeRequest:
      type: object
      properties:
        name:
          type: string
        description:
          type: string
        status:
          type: string
          enum:
            - public
            - private
        model:
          type: string
        messages:
          type: array
          items:
            $ref: '#/components/schemas/Message'
        tools:
          type: array
          items:
            type: object
        memory:
          type: array
          items:
            type: object
      required:
        - name
    Memory:
      type: object
      properties:
        name:
          type: string
        description:
          type: string
        embeddingModel:
          type: string
    CreateMemoryRequest:
      type: object
      properties:
        name:
          type: string
        description:
          type: string
        embeddingModel:
          type: string
          example: openai:text-embedding-3-large
      required:
        - name
    RetrieveMemoryRequest:
      type: object
      properties:
        query:
          type: string
        memory:
          type: array
          items:
            type: object
            properties:
              name:
                type: string
        topK:
          type: integer
          default: 20
          minimum: 1
          maximum: 100
        filters:
          type: array
          items:
            type: object
      required:
        - query
        - memory
    RetrievedChunk:
      type: object
      properties:
        text:
          type: string
        similarity:
          type: number
          format: float
        meta:
          type: object
          additionalProperties:
            type: string
    Document:
      type: object
      properties:
        name:
          type: string
        status:
          type: string
          enum:
            - queued
            - in_progress
            - completed
            - failed
        enabled:
          type: boolean
    Thread:
      type: object
      properties:
        id:
          type: string
        metadata:
          type: object
          additionalProperties:
            type: string
        createdAt:
          type: integer
    CreateThreadRequest:
      type: object
      properties:
        metadata:
          type: object
          additionalProperties:
            type: string
        messages:
          type: array
          items:
            $ref: '#/components/schemas/Message'
    WebSearchRequest:
      type: object
      properties:
        query:
          type: string
        service:
          type: string
          enum:
            - exa
        totalResults:
          type: integer
        domains:
          type: array
          items:
            type: string
      required:
        - query
        - service
    CrawlRequest:
      type: object
      properties:
        url:
          type: array
          items:
            type: string
        service:
          type: string
          enum:
            - spider
        maxPages:
          type: integer
      required:
        - url
        - service
    WebSearchResult:
      type: object
      properties:
        url:
          type: string
        content:
          type: string
    ParseResponse:
      type: object
      properties:
        documentName:
          type: string
        content:
          type: string
    ChunkRequest:
      type: object
      properties:
        content:
          type: string
        chunkMaxLength:
          type: integer
          default: 1024
          minimum: 1024
          maximum: 30000
        chunkOverlap:
          type: integer
          default: 256
          minimum: 256
      required:
        - content
    EmbedRequest:
      type: object
      properties:
        chunks:
          type: array
          items:
            type: string
          maxItems: 100
        embeddingModel:
          type: string
          default: openai:text-embedding-3-large
      required:
        - chunks
    DeleteResponse:
      type: object
      properties:
        success:
          type: boolean
        name:
          type: string