Letta

Letta Archival Memory API

Out-of-context long-term memory archives and passages.

GitHub OpenAPI

Operations 9

POST /v1/archives/ Create Archive
GET /v1/archives/ List Archives
GET /v1/archives/{archive_id} Retrieve Archive
PATCH /v1/archives/{archive_id} Modify Archive
DELETE /v1/archives/{archive_id} Delete Archive
GET /v1/archives/{archive_id}/agents List Agents For Archive
POST /v1/archives/{archive_id}/passages Create Passage In Archive
POST /v1/archives/{archive_id}/passages/batch Create Passages In Archive
DELETE /v1/archives/{archive_id}/passages/{passage_id} Delete Passage From Archive

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/letta/refs/heads/main/openapi/letta-archival-memory-api-openapi.yml

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OpenAPI Specification

letta-archival-memory-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Letta Agent Templates Archival Memory API
  description: The Letta API creates and operates stateful AI agents whose memory - core context blocks and archival vector memory - persists across sessions. It configures the tools, data sources, identities, and multi-agent groups an agent uses, sends and streams messages to agents, and inspects the runs, jobs, and steps behind every agent response. The same OpenAPI-documented interface is served by the managed Letta Cloud API and by the open-source, self-hostable Letta server. All requests require a Bearer API key.
  version: 1.0.0
  contact:
    name: Letta
    url: https://www.letta.com
  license:
    name: Apache-2.0
    url: https://github.com/letta-ai/letta/blob/main/LICENSE
servers:
- url: https://api.letta.com/v1
  description: Letta Cloud
- url: http://localhost:8283/v1
  description: Self-hosted (default local port)
security:
- bearerAuth: []
tags:
- name: Archival Memory
  description: Out-of-context long-term memory archives and passages.
paths:
  /v1/archives/:
    post:
      tags:
      - Archival Memory
      summary: Create Archive
      description: Create a new archive.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Archive'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '422':
          $ref: '#/components/responses/ValidationError'
    get:
      tags:
      - Archival Memory
      summary: List Archives
      description: Get a list of all archives for the current organization with optional filters and pagination.
      parameters:
      - name: before
        in: query
        required: false
        description: Archive ID cursor for pagination. Returns archives that come before this archive ID in the specified sort order
        schema:
          type: string
      - name: after
        in: query
        required: false
        description: Archive ID cursor for pagination. Returns archives that come after this archive ID in the specified sort order
        schema:
          type: string
      - name: limit
        in: query
        required: false
        description: Maximum number of archives to return
        schema:
          type: string
          default: 50
      - name: order
        in: query
        required: false
        description: Sort order for archives by creation time. 'asc' for oldest first, 'desc' for newest first
        schema:
          type: string
          default: desc
          enum:
          - asc
          - desc
      - name: order_by
        in: query
        required: false
        description: Field to sort by
        schema:
          type: string
          default: created_at
      - name: name
        in: query
        required: false
        description: Filter by archive name (exact match)
        schema:
          type: string
      - name: agent_id
        in: query
        required: false
        description: Only archives attached to this agent ID
        schema:
          type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/Archive'
        '401':
          $ref: '#/components/responses/Unauthorized'
  /v1/archives/{archive_id}:
    get:
      tags:
      - Archival Memory
      summary: Retrieve Archive
      description: Get a single archive by its ID.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Archive'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
    patch:
      tags:
      - Archival Memory
      summary: Modify Archive
      description: Update an existing archive's name and/or description.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Archive'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '422':
          $ref: '#/components/responses/ValidationError'
    delete:
      tags:
      - Archival Memory
      summary: Delete Archive
      description: Delete an archive by its ID.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
  /v1/archives/{archive_id}/agents:
    get:
      tags:
      - Archival Memory
      summary: List Agents For Archive
      description: Get a list of agents that have access to an archive with pagination support.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      - name: before
        in: query
        required: false
        description: Agent ID cursor for pagination. Returns agents that come before this agent ID in the specified sort order
        schema:
          type: string
      - name: after
        in: query
        required: false
        description: Agent ID cursor for pagination. Returns agents that come after this agent ID in the specified sort order
        schema:
          type: string
      - name: limit
        in: query
        required: false
        description: Maximum number of agents to return
        schema:
          type: string
          default: 50
      - name: order
        in: query
        required: false
        description: Sort order for agents by creation time. 'asc' for oldest first, 'desc' for newest first
        schema:
          type: string
          default: desc
          enum:
          - asc
          - desc
      - name: include
        in: query
        required: false
        description: Specify which relational fields to include in the response. No relationships are included by default.
        schema:
          type: array
          default: []
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
  /v1/archives/{archive_id}/passages:
    post:
      tags:
      - Archival Memory
      summary: Create Passage In Archive
      description: Create a new passage in an archive.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Passage'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/archives/{archive_id}/passages/batch:
    post:
      tags:
      - Archival Memory
      summary: Create Passages In Archive
      description: Create multiple passages in an archive.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/Passage'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/archives/{archive_id}/passages/{passage_id}:
    delete:
      tags:
      - Archival Memory
      summary: Delete Passage From Archive
      description: Delete a passage from an archive.
      parameters:
      - name: archive_id
        in: path
        required: true
        description: The ID of the archive in the format 'archive-<uuid4>'
        schema:
          type: string
      - name: passage_id
        in: path
        required: true
        description: The ID of the passage in the format 'passage-<uuid4>'
        schema:
          type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
components:
  schemas:
    Archive:
      type: object
      description: An agent's out-of-context, searchable long-term memory archive.
      properties:
        id:
          type: string
        name:
          type: string
        description:
          type: string
        vector_db_provider:
          type: string
        embedding_config:
          type: object
          additionalProperties: true
        metadata:
          type: object
          additionalProperties: true
        created_at:
          type: string
          format: date-time
    HTTPValidationError:
      type: object
      properties:
        detail:
          type: array
          items:
            type: object
            properties:
              loc:
                type: array
                items:
                  type: string
              msg:
                type: string
              type:
                type: string
    Error:
      type: object
      properties:
        error:
          type: object
          properties:
            message:
              type: string
            code:
              type: string
    Passage:
      type: object
      description: A single unit of archival memory - a chunk of text with its embedding.
      properties:
        id:
          type: string
        text:
          type: string
        archive_id:
          type: string
        source_id:
          type: string
        file_id:
          type: string
        file_name:
          type: string
        tags:
          type: array
          items:
            type: string
        metadata:
          type: object
          additionalProperties: true
        created_at:
          type: string
          format: date-time
  responses:
    ValidationError:
      description: The request payload failed validation.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/HTTPValidationError'
    Unauthorized:
      description: Missing or invalid Bearer API key.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    NotFound:
      description: The requested resource was not found.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'API key created at https://app.letta.com/api-keys, passed as `Authorization: Bearer YOUR_API_KEY`.'