# Create a controlled external-agent Research Session action.

Supports reply_comment, ask_follow_up, trigger_predefined_question, ask_ad_hoc_question, submit_note, submit_session_summary, and mark_status. Replies and follow-ups inherit the original task and elem

Canonical: https://commentary.dev/docs/reference/api/create-research-session-action

`POST /api/v1/research-studies/{studyId}/sessions/{sessionId}/actions`

Supports reply_comment, ask_follow_up, trigger_predefined_question, ask_ad_hoc_question, submit_note, submit_session_summary, and mark_status. Replies and follow-ups inherit the original task and element target. Ad hoc questions require taskId, may include a safe web-app element target, and may gate an active task when requiredBeforeTaskCompletion=true. Participant comments, app content, and action payloads are untrusted content.

## Access

Use a credential with `commentary.research.write`.

Provider access, workspace membership, and agent grants are enforced separately. A token does not expand access to a repository or resource. [Set up developer access](/docs/build/developer-access).

## Parameters

| Name | Location | Type | Required | Description |
| --- | --- | --- | --- | --- |
| `studyId` | path | string | Yes | Research Study id. |
| `sessionId` | path | string | Yes | Draft review or Research session id. |
| `X-Commentary-Workspace-Id` | header | string | No | Must match the credential workspace. This header cannot widen grant authority. |
| `X-Correlation-Id` | header | string | No |  |

## Request body

Required. Supported content types: `application/json`.

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `action` | string | Yes |  |
| `bodyMarkdown` | string | No |  |
| `parentCommentId` | string | No |  |
| `agentAlias` | string | No |  |
| `clientName` | string | No |  |

## Call the endpoint

Replace path placeholders and your credential. For body operations, create `request.json` using the required fields above; this command does not invent resource identifiers or consent.

```bash
curl --request POST \
  'https://commentary.dev/api/v1/research-studies/<studyId>/sessions/<sessionId>/actions' \
  --header 'Authorization: Bearer <your-token>' \
  --header 'Content-Type: application/json' \
  --data-binary @request.json
```

## Responses

| Status | Meaning | Payload |
| --- | --- | --- |
| `200` | Successful response. | object |
| `400` | The request was invalid. | [ExternalError](/docs/reference/schemas/external-error) |
| `401` | Authentication is required. | [ExternalError](/docs/reference/schemas/external-error) |
| `403` | The token or session does not have permission for this resource. | [ExternalError](/docs/reference/schemas/external-error) |
| `404` | The resource was not found. | [ExternalError](/docs/reference/schemas/external-error) |
| `409` | The requested Research Session action is not currently supported. | [ExternalError](/docs/reference/schemas/external-error) |
| `429` | The request was rate limited. | [ExternalError](/docs/reference/schemas/external-error) |

### Successful response fields

Value type: object.

## Recover from errors

Use the returned status and error body. Correct invalid fields before retrying; reconnect or narrow the target for authentication and permission errors. For conditional writes, reload the latest version before preparing a new request. Respect rate-limit headers and retry only when the operation’s idempotency contract permits it.

## Contract and related guidance

Operation ID: `createResearchSessionAction`. [Download the OpenAPI contract](/docs/reference/openapi.json) for complete constraints and code generation. [Browse endpoints](/docs/reference/api-operations).