Get session messages

GET /api/v1/projects/{id}/sessions/{session_id}/messages
Bearer auth

Fetches all messages for a specific session via the workspace Orchestration Engine. The project scope is carried by the route id path parameter and the org is derived from that project.

Path parameters

  • id string Required

    Project ID

  • session_id string Required

    Session ID

Query parameters

  • workspace_id string

    Workspace ID for workspace resolution

Responses

  • 406

    Unsupported or malformed API version, an operation unavailable in the selected published contract, or an unacceptable representation (including unsupported media-type parameters or excluded SSE). Existing authentication, authorization, and rate-limit failures take precedence.

    Hide response attributes Show response attributes object
    • badRequestDetail object

      Optional validation details defined by the standard error schema; API negotiation errors do not emit this field.

      Hide badRequestDetail attribute Show badRequestDetail attribute object
      • fields array[object]

        Fields with validation failures.

        Hide fields attributes Show fields attributes object

        A field and its validation failure.

        • description string Required

          Human-readable validation failure.

        • field string Required

          Name or path of the invalid request field.

    • detail string Required

      Human-readable error details.

    • error integer Required

      HTTP status code.

    • errorCode string Required

      Machine-readable error code.

    • parameters array[string]

      Request parameter names associated with the error; omitted when none apply.

    • reason string Required

      HTTP status reason phrase.

    Hide response attributes Show response attributes object
    • badRequestDetail object

      Optional validation details defined by the standard error schema; API negotiation errors do not emit this field.

      Hide badRequestDetail attribute Show badRequestDetail attribute object
      • fields array[object]

        Fields with validation failures.

        Hide fields attributes Show fields attributes object

        A field and its validation failure.

        • description string Required

          Human-readable validation failure.

        • field string Required

          Name or path of the invalid request field.

    • detail string Required

      Human-readable error details.

    • error integer Required

      HTTP status code.

    • errorCode string Required

      Machine-readable error code.

    • parameters array[string]

      Request parameter names associated with the error; omitted when none apply.

    • reason string Required

      HTTP status reason phrase.
  • 200

    OK

    Hide response attributes Show response attributes object
    • history_status string

      HistoryStatus reports whether Messages is authoritative or still warming.

    • latest_status string

      LatestStatus is the status of the session's most recent execution.

    • messages array[object]
      Hide messages attributes Show messages attributes object
      • additional_kwargs object

        Additional properties are allowed.

      • content string
      • id string
      • name string

        Tool name for tool messages

      • role string
      • session_id string
      • timestamp string
      • tool_call_id string
      • tool_calls array[object]
        Hide tool_calls attributes Show tool_calls attributes object
        • id string
        • index integer
        • name string
        • type string
    Hide response attributes Show response attributes object
    • history_status string

      HistoryStatus reports whether Messages is authoritative or still warming.

    • latest_status string

      LatestStatus is the status of the session's most recent execution.

    • messages array[object]
      Hide messages attributes Show messages attributes object
      • additional_kwargs object

        Additional properties are allowed.

      • content string
      • id string
      • name string

        Tool name for tool messages

      • role string
      • session_id string
      • timestamp string
      • tool_call_id string
      • tool_calls array[object]
        Hide tool_calls attributes Show tool_calls attributes object
        • id string
        • index integer
        • name string
        • type string
  • 400

    Bad Request

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    • code string
    • error string
    • success boolean
    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
  • 401

    Unauthorized

    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
  • 422

    PROJECT_SECRET_INVALID: the workspace cannot start because a project secret is invalid or unreachable (fix the secret and redeploy)

    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
  • 500

    Internal Server Error

    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
  • 502

    Bad Gateway

    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
    Hide response attributes Show response attributes object
    • code string
    • error string
    • success boolean
GET /api/v1/projects/{id}/sessions/{session_id}/messages 
curl \
 --request GET 'https://agentengine.mongodb.com/api/v1/projects/{id}/sessions/{session_id}/messages' \
 --header "Authorization: $API_KEY"
Response examples (406) 
{
  "detail": "This operation is not available in API version 2026-09-20-preview.",
  "error": 406,
  "errorCode": "OPERATION_NOT_IN_API_VERSION",
  "parameters": [
    "Accept"
  ],
  "reason": "Not Acceptable"
}
{
  "detail": "This operation supports text/event-stream, which the Accept header excludes. Remove unsupported media-type parameters or accept this type with a positive q value.",
  "error": 406,
  "errorCode": "UNACCEPTABLE_MEDIA_TYPE",
  "parameters": [
    "Accept"
  ],
  "reason": "Not Acceptable"
}
{
  "detail": "The requested API version is not supported. Supported versions: 2026-09-20-preview.",
  "error": 406,
  "errorCode": "UNSUPPORTED_API_VERSION",
  "parameters": [
    "Accept"
  ],
  "reason": "Not Acceptable"
}
Response examples (406) 
{
  "detail": "This operation is not available in API version 2026-09-20-preview.",
  "error": 406,
  "errorCode": "OPERATION_NOT_IN_API_VERSION",
  "parameters": [
    "Accept"
  ],
  "reason": "Not Acceptable"
}
Response examples (200) 
{
  "history_status": "string",
  "latest_status": "string",
  "messages": [
    {
      "additional_kwargs": {},
      "content": "string",
      "id": "string",
      "name": "string",
      "role": "string",
      "session_id": "string",
      "timestamp": "string",
      "tool_call_id": "string",
      "tool_calls": [
        {
          "id": "string",
          "index": 42,
          "name": "string",
          "type": "string"
        }
      ]
    }
  ]
}
Response examples (200) 
{
  "history_status": "string",
  "latest_status": "string",
  "messages": [
    {
      "additional_kwargs": {},
      "content": "string",
      "id": "string",
      "name": "string",
      "role": "string",
      "session_id": "string",
      "timestamp": "string",
      "tool_call_id": "string",
      "tool_calls": [
        {
          "id": "string",
          "index": 42,
          "name": "string",
          "type": "string"
        }
      ]
    }
  ]
}
Response examples (400) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (400) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (401) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (401) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (422) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (422) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (500) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (500) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (502) 
{
  "code": "string",
  "error": "string",
  "success": true
}
Response examples (502) 
{
  "code": "string",
  "error": "string",
  "success": true
}