---
title: "Start Run"
method: POST
path: "/api/v1/simulation/runs"
tags: ["simulation"]
---

# Start Run

`POST /api/v1/simulation/runs`

## Request

- Base URL: `https://cp.xenovia.io` (the document declares no server; this is the origin it was published from)
- URL: `https://cp.xenovia.io/api/v1/simulation/runs`
- Auth: none declared

## Headers

- `Authorization` string, nullable
- `X-Request-ID` string, nullable

## Request body

- RunCreate: The suite's agent runs it. No scenario_ids: every active scenario of the suite. No provider_id: the agent's own provider (its model is recorded on the run). mode enforce: policies and guardrails block as in production; observe: they record and block nothing.
  - `suite_id` string, uuid, required
  - `agent_id` string, uuid, nullable
  - `scenario_ids` string[], nullable
  - `provider_id` string, uuid, nullable
  - `mode` 'enforce' | 'observe'
  - `trials` integer

## Response `201`

Successful Response

- unknown

## Other responses

- `422`: Validation Error

## Changes

- **2026-10-26** `3e25bef24f8f`: 2 info
  - the request property `agent_id` became optional
  - request property `agent_id` list-of-types was widened by adding types `null` to media type `application/json`
- **2026-10-08** `1882866431ad`: 3 warning, 1 info
  - removed the request property `early_stop`
  - removed the request property `faults`
  - removed the request property `strategies`
  - the `mode` request property default value changed from `observe` to `enforce`
- **2026-10-08** `a141cb4fdc6a`: 3 info
  - added the new optional request property `early_stop`
  - added the new optional request property `faults`
  - added the new optional request property `strategies`
- **2026-10-04** `b475b750a0b7`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/xenovia/apis/controlplane/changes/api/v1/simulation/runs/post.md)

---

[API](https://skmtc.dev/xenovia/apis/controlplane.md) - [All operations](https://skmtc.dev/xenovia/apis/controlplane/llms.txt) - [OpenAPI document](https://skmtc.dev/xenovia/apis/controlplane/revisions/3e25bef24f8f?raw)