---
title: "Provider-neutral control plane for hosted ALK harness jobs."
method: POST
path: "/simulate/api/harness-jobs/{id}/extend/"
tags: ["simulate"]
---

# Provider-neutral control plane for hosted ALK harness jobs.

`POST /simulate/api/harness-jobs/{id}/extend/`

## Request

- Base URL: `http://localhost:8000`
- URL: `http://localhost:8000/simulate/api/harness-jobs/{id}/extend/`
- Auth: one of:
  - API key in header `X-Api-Key`
  - API key in header `X-Secret-Key`

Validates the v1.6 request contract and delegates execution to the public backend selected by
``settings.HARNESS_PROVIDER`` (``hosted`` or ``sandbox``). The hosted backend independently
selects its managed sandbox runtime.

## Request body

- HarnessJobExtend
  - `count` integer, required: How many new scenarios to add to the saved world.
  - `guidance` string: Optional natural-language steering for the added scenarios (e.g. 'calm first-time riders booking an airport pickup'). Existing scenarios are preserved.
  - `client_request_id` string

## Response `201`

Created

- HarnessJobExtend
  - `count` integer, required: How many new scenarios to add to the saved world.
  - `guidance` string: Optional natural-language steering for the added scenarios (e.g. 'calm first-time riders booking an airport pickup'). Existing scenarios are preserved.
  - `client_request_id` string

## Other responses

- `default`: Default error response

---

[API](https://skmtc.dev/futureagi/apis/future-agi-management-api.md) · [All operations](https://skmtc.dev/futureagi/apis/future-agi-management-api/llms.txt) · [OpenAPI document](https://skmtc.dev/futureagi/apis/future-agi-management-api/revisions/c8684118e142?raw)