---
title: "Set cohort username"
method: POST
path: "/v1/competitions/{slug}/cohort-username"
tags: ["Competition"]
---

# Set cohort username

`POST /v1/competitions/{slug}/cohort-username`

## Request

- Base URL: `https://api.testnet.rise.trade`
- URL: `https://api.testnet.rise.trade/v1/competitions/{slug}/cohort-username`
- Auth: none required
- TypeScript: <https://skmtc.dev/rise/apis/risex-rest-api/docs/v1/competitions/:slug/cohort-username/post.ts> (a function with typed inputs; its response is checked against the schema)

Set a username for a wallet in a cohort-whitelisted competition (one whose scoring_config sets participant_cohort_flag_key). Requires a valid session for the named wallet. Fails with PERMISSION_DENIED if the wallet isn't in that competition's cohort or doesn't match the authenticated session, or FAILED_PRECONDITION if the competition has no cohort whitelist at all.

## Path parameters

- `slug` string, required

## Request body

- CompetitionServiceSetCohortUsernameBody
  - `wallet` string: Wallet address (0x-prefixed). Must already be in that competition's cohort whitelist.
  - `username` string

## Response `200`

A successful response.

- ApiSetCohortUsernameResponse
  - `wallet` string
  - `username` string

## Other responses

- `default`: An unexpected error response.

## Changes

- **2026-11-03** `98eabcd6a6ad`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/rise/apis/risex-rest-api/changes/v1/competitions/:slug/cohort-username/post.md)

---

[API](https://skmtc.dev/rise/apis/risex-rest-api.md) - [All operations](https://skmtc.dev/rise/apis/risex-rest-api/llms.txt) - [OpenAPI document](https://skmtc.dev/rise/apis/risex-rest-api/revisions/98eabcd6a6ad?raw)