List thread steps
GET
/v1/threads/{threadId}/stepsList first-class thread history steps and timeline anchors.
How to call this endpoint
Every ACP API request uses bearer authentication. The examples here show the actual request path, auth header, and body shape that the platform expects.
Path, query, and header parameters
These parameters control which ACP object the endpoint acts on and how the request is processed.
Path parameters
| Name | Location | Type | Required | Description |
|---|---|---|---|---|
| threadId | path | string | Yes | Thread ID |
Query parameters
| Name | Location | Type | Required | Description |
|---|---|---|---|---|
| limit | query | integer | No | — |
| offset | query | integer | No | — |
| compact | query | boolean | No | Return compact step metadata. |
Body schema
This endpoint does not require a request body.
None.
What the API returns
Each response code below includes the documented payload shape for the ACP API.
200Thread step listapplication/json
| Field | Type | Required | Description |
|---|---|---|---|
| object | string | No | — |
| data | object[] | No | — |
| data[].id | string | No | Unique identifier. |
| data[].threadId | string | No | Thread ID. |
| data[].environmentId | string | No | Computer ID. |
| data[].sequence | integer | No | — |
| data[].sourceMessageId | string | No | — |
| data[].stepKind | user_message | assistant_message | reasoning | command_execution | mcp_tool_call | file_change | turn_completed | system | other | No | — |
| data[].eventType | string | No | — |
| data[].title | string | No | Display title. |
| data[].snapshotBeforeId | string | No | — |
| data[].snapshotAfterId | string | No | — |
| data[].metadata | object | No | Free-form metadata object. |
| data[].createdAt | string | No | ISO 8601 timestamp. |