---
title: "Register a namespace (idempotent)"
method: PUT
path: "/api/v1alpha/namespaces/{namespace}"
tags: ["Namespaces"]
---

# Register a namespace (idempotent)

`PUT /api/v1alpha/namespaces/{namespace}`

Ensures the namespace exists in active_namespaces. Creates it and returns 201 if new; returns 200 if it already existed. Safe to call repeatedly.

## Path parameters

- `namespace` string, required

## Response `200`

Namespace already existed

## Other responses

- `201` — Namespace registered
- `401` — Unauthorized
- `403` — Forbidden - requires MANAGE_CI

---

[API](https://skmtc.net/hail-is/apis/hail-ci-service.md) · [All operations](https://skmtc.net/hail-is/apis/hail-ci-service/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/hail-is/hail-ci-service/versions/37d6dddb7b5a/schema)