---
title: "Cancel Tune"
method: POST
path: "/tune/{session_id}/cancel"
tags: ["tune"]
---

# Cancel Tune

`POST /tune/{session_id}/cancel`

## Path parameters

- `session_id` string, required

## Response `200`

Cancellation requested

## Other responses

- `400` — Cannot cancel from current status
- `404` — Session not found
- `409` — Session is not a tune session — its metadata is missing an explicit `kind == "tune"` discriminator. Sessions created via `/pipeline` or `/predict` (or via the bare `SessionManager.create_session()` default) cannot be cancelled through this route; use POST /pipeline/{session_id}/cancel or POST /predict/{session_id}/cancel instead.

## Changes

- **2026-05-27** `bef81aa36f74` — 1 info
  - endpoint added
- **2026-04-29** `0ba9e71b823c` — 1 breaking
  - api path removed without deprecation

[Change history](https://skmtc.dev/nvidia/apis/physics-agent-service/changes/tune/:session_id/cancel/post.md)

---

[API](https://skmtc.dev/nvidia/apis/physics-agent-service.md) · [All operations](https://skmtc.dev/nvidia/apis/physics-agent-service/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/nvidia/physics-agent-service/revisions/47f3bc191c91/schema)