---
title: "Cancel running simulation"
method: POST
path: "/api/v1/simulation/cancel"
tags: ["simulation"]
---

# Cancel running simulation

`POST /api/v1/simulation/cancel`

## Request

- Base URL: `https://api.helena.bio` (the document declares no server; this is the origin it was published from)
- URL: `https://api.helena.bio/api/v1/simulation/cancel`
- Auth: HTTP bearer

Initiate cancellation of running simulation.

Non-blocking: sends SIGTERM and returns immediately with status='cancelling'.
Background watcher handles graceful shutdown (up to 30s grace period) and
falls back to SIGKILL if subprocess does not respond. Status endpoint
returns 'cancelling' during grace period, 'cancelled' after subprocess exits.

CR-2026-SIMVIEW-CANCEL-001

## Response `200`

Successful Response

- SimulationStatusResponse
  - `run_id` string, required
  - `status` string, required
  - `cr_id` string, nullable
  - `progress_current` integer
  - `progress_total` integer
  - `elapsed_seconds` number
  - `result` object, nullable
  - `error` string, nullable
  - `log_lines` string[], nullable

---

[API](https://skmtc.dev/helena/apis/helix-insight-variant-analysis-service.md) · [All operations](https://skmtc.dev/helena/apis/helix-insight-variant-analysis-service/llms.txt) · [OpenAPI document](https://skmtc.dev/helena/apis/helix-insight-variant-analysis-service/revisions/fe51fd20cdf1?raw)