---
title: "Inspect TUI and Chat interface handoff support and progress"
method: GET
path: "/api/v1/sessions/{sessionId}/interface-transition"
tags: ["sessions"]
---

# Inspect TUI and Chat interface handoff support and progress

`GET /api/v1/sessions/{sessionId}/interface-transition`

## Path parameters

- `sessionId` string, required — Session identifier, e.g. project-1.

## Response `200`

OK

- SessionInterfaceTransitionStatusResponse
  - `reason` string
  - `reasonCode` string
  - `supported` boolean, required
  - `targetMode` 'chat' | 'tui', required
  - `transition` SessionInterfaceTransition
    - `completedAt` string, date-time, nullable
    - `createdAt` string, date-time, required
    - `errorCode` string
    - `errorDetail` string
    - `historyPolicy` 'strict' | 'provider_history', required
    - `id` string, required
    - `noticeAcknowledgedAt` string, date-time, nullable
    - `phase` 'requested' | 'preflighting' | 'draining' | 'source_stopping' | 'source_stopped' | 'target_starting' | 'activating' | 'completed' | 'failed' | 'cancelled' | 'recovery_required', required
    - `policy` 'drain' | 'interrupt', required
    - `sessionId` string, required
    - `sourceMode` 'chat' | 'tui', required
    - `targetMode` 'chat' | 'tui', required
    - `updatedAt` string, date-time, required

## Other responses

- `404` — Not Found
- `409` — Conflict
- `500` — Internal Server Error
- `501` — Not Implemented

## Changes

- **2026-09-14** `fe5d127437ea` — 1 info
  - added the required property `transition/historyPolicy` to the response with the `200` status
- **2026-09-03** `d31a2d019c47` — 4 info
  - added the optional property `reporting_owner` to the response with the `404` status
  - added the optional property `reporting_owner` to the response with the `409` status
  - added the optional property `reporting_owner` to the response with the `500` status
  - added the optional property `reporting_owner` to the response with the `501` status
- **2026-08-17** `afadfb858881` — 1 info
  - added the optional property `transition/noticeAcknowledgedAt` to the response with the `200` status
- **2026-08-06** `d8396ad2c721` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/composiohq/apis/agent-orchestrator-http-daemon/changes/api/v1/sessions/:sessionId/interface-transition/get.md)

---

[API](https://skmtc.dev/composiohq/apis/agent-orchestrator-http-daemon.md) · [All operations](https://skmtc.dev/composiohq/apis/agent-orchestrator-http-daemon/llms.txt) · [OpenAPI document](https://skmtc.dev/composiohq/apis/agent-orchestrator-http-daemon/revisions/36b3a9d49c3e?raw)