Site creation can answer 202
POST /v1/sites copies the starter template into the site’s Git repository before it returns. That usually takes a few seconds. When it takes more than 20 seconds, the request now answers 202 Accepted with the new site’s id instead of the site:
GET /v1/sites a few seconds later; the site appears there, with its clone_url, once it is ready. Do not create it again. A site that finishes within 20 seconds still answers 201 with the site, as before.
Migration
Requests pinned to2026-10-29 or earlier never receive a 202. When creation takes more than 20 seconds they get 503 service_unavailable with no Retry-After header, and the error message names the site’s id. The site still finishes: check GET /v1/sites before retrying, or you create a second site.
The MCP create_site tool answers { "object": "site", "id": …, "status": "creating" } in the same case; call list_sites shortly to get the site.