---
title: "Register what you're comparing before the hidden test is used (one registration, one run)"
method: POST
path: "/v1/hidden/{id}/register"
---

# Register what you're comparing before the hidden test is used (one registration, one run)

`POST /v1/hidden/{id}/register`

## Request

- Base URL: `https://api.reasonblocks.com`
- URL: `https://api.reasonblocks.com/v1/hidden/{id}/register`
- Auth: HTTP bearer

## Path parameters

- `id` string, required

## Query parameters

- `project` string

## Request body

- object
  - `baseline` string
  - `candidate` string
  - `min_gain` number
  - `confidence` number
  - `change` string
  - `bar` object

## Response `201`

registration_id

## Changes

- **2026-11-02** `596a08a02857`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/reasonblocks/apis/reasonblocks-control-plane-api/changes/v1/hidden/:id/register/post.md)

---

[API](https://skmtc.dev/reasonblocks/apis/reasonblocks-control-plane-api.md) - [All operations](https://skmtc.dev/reasonblocks/apis/reasonblocks-control-plane-api/llms.txt) - [OpenAPI document](https://skmtc.dev/reasonblocks/apis/reasonblocks-control-plane-api/revisions/596a08a02857?raw)