---
title: "Initialize the simulation"
method: PUT
path: "/initialize/{testid}"
tags: ["management"]
---

# Initialize the simulation

`PUT /initialize/{testid}`

Initialize simulation to a start time using a warmup period (also resets history and KPI calculations).

## Request body

- object
  - `start_time` number, required — Start time (epoch seconds) to initialize the simulation to.
  - `warmup_period` number, required — Warmup period in seconds.

## Response `200`

Simulation initialized successfully.

- StepResponse
  - `message` string — A message describing the response.
  - `payload` object — Current values of all input and measurement signals; always includes "time".
    - `time` number, required — Current simulation time (epoch seconds).
  - `status` integer — HTTP status code.

## Changes

- **2025-12-18** `e979b6db7bfd` — 1 info
  - added the required property `payload/time` to the response with the `200` status
- **2025-11-18** `6f370686638c` — 1 info
  - api tag `management` added
- **2025-11-18** `addf0e2239dd` — 3 breaking
  - the request property `start_time` became required
  - the request property `warmup_period` became required
  - the `payload` response's property type changed from `string` to `object` for status `200`
- **2025-11-18** `60d61eda81c7` — 2 breaking, 3 info
  - the `payload` response's property type changed from `object` to `string` for status `200`
  - removed the required property `payload/time` from the response with the `200` status
  - api tag `Test Setup` removed
  - the request property `start_time` became optional
  - …1 more

[Change history](https://skmtc.dev/ibpsa/apis/boptest-service-api/changes/initialize/:testid/put.md)

---

[API](https://skmtc.dev/ibpsa/apis/boptest-service-api.md) · [All operations](https://skmtc.dev/ibpsa/apis/boptest-service-api/llms.txt) · [OpenAPI document](https://skmtc.dev/ibpsa/apis/boptest-service-api/revisions/e979b6db7bfd?raw)