---
title: "Changes to Compact Agent Session"
method: POST
path: "/v1/agent_sessions/{session_id}/compact"
---

# Changes to Compact Agent Session

`POST /v1/agent_sessions/{session_id}/compact`

> Every recorded change to this endpoint, newest first.

## Timeline

Changed in 4 of 70 revisions.

- **2026-08-28** `4016becf04d6` — 1 info
- **2026-08-25** `e4bf71c6ae16` — 2 info
- **2026-08-21** `6107b5235c74` — 1 warning
- **2026-08-11** `881c8eca3876` — 1 info

## Changes

- **2026-08-28** `4016becf04d6` — 1 info
  - added the optional property `data/parts/items/anyOf[subschema #2: ReasoningUIPart]/id` to the response with the `200` status
- **2026-08-25** `e4bf71c6ae16` — 2 info
  - added the optional property `data/metadata/anyOf[subschema #1: MessageMetadata]/phoenix/anyOf[subschema #1]/oneOf[subschema #2: PhoenixUserMessageMetadata]/editPermission` to the response with the `200` status
  - added the optional property `data/metadata/anyOf[subschema #1: MessageMetadata]/phoenix/anyOf[subschema #1]/oneOf[subschema #2: PhoenixUserMessageMetadata]/uiContexts` to the response with the `200` status
- **2026-08-21** `6107b5235c74` — 1 warning
  - added the new `agent_session_tool_approvals_conflict` enum value to the `code` response property for the response status `409`
- **2026-08-11** `881c8eca3876` — 1 info
  - endpoint added

---

[Operation](https://skmtc.dev/arize-ai/apis/arize-phoenix-rest-api/docs/v1/agent_sessions/:session_id/compact/post.md) · [API](https://skmtc.dev/arize-ai/apis/arize-phoenix-rest-api.md) · [Page](https://skmtc.dev/arize-ai/apis/arize-phoenix-rest-api/changes/v1/agent_sessions/:session_id/compact/post)