# `GET /v1/sessions/{sessionId}/stream` — Observe a session

Part of the [Bkper Managed Agent API](https://bkper.com/docs/api/managed-agent.md). Read its guide for authentication, conventions, and examples.

Authenticated-fetch SSE: one `snapshot` (Snapshot), then coalesced `update` events (Update). A new snapshot follows lag. Expires after five minutes; disconnecting never cancels work.

## Operation contract

```json
{
  "operationId": "observeSession",
  "tags": [
    "Streams"
  ],
  "summary": "Observe a session",
  "security": [
    {
      "bearerAuth": []
    }
  ],
  "parameters": [
    {
      "name": "sessionId",
      "in": "path",
      "required": true,
      "schema": {
        "type": "string"
      }
    }
  ],
  "responses": {
    "200": {
      "description": "SSE",
      "content": {
        "text/event-stream": {
          "schema": {
            "type": "string"
          }
        }
      }
    },
    "400": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "401": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "403": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "404": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "409": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "410": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "411": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "413": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    },
    "503": {
      "description": "Rejected; never contains credentials or upstream payloads.",
      "content": {
        "application/json": {
          "schema": {
            "$ref": "#/components/schemas/Error"
          }
        }
      }
    }
  },
  "description": "Authenticated-fetch SSE: one `snapshot` (Snapshot), then coalesced `update` events (Update). A new snapshot follows lag. Expires after five minutes; disconnecting never cancels work."
}
```

## Schemas

### Error

```json
{
  "type": "object",
  "properties": {
    "error": {
      "type": "object",
      "properties": {
        "code": {
          "type": "string",
          "description": "Stable code, e.g. not_found, idempotency_conflict, session_working, usage_limit_exceeded. Open."
        },
        "type": {
          "description": "Category, e.g. invalid_request_error, authentication_error, usage_limit_error. Open.",
          "type": "string"
        },
        "message": {
          "type": "string"
        }
      },
      "required": [
        "code"
      ]
    }
  },
  "required": [
    "error"
  ]
}
```

## Authentication

```json
{
  "bearerAuth": {
    "type": "http",
    "scheme": "bearer"
  }
}
```