* fix(copilot): restore generic endpoint for non-subscription OAuth (#610)
0.23.0 re-pointed the shared Copilot OAuth branch from the generic
api.githubcopilot.com host to the account-specific endpoints.api host
returned by /copilot_internal/user, and made resolve_copilot_api_url
ignore the GITHUB_COPILOT_API_URL override whenever a token resolved.
That change was meant to add --subscription, but it also altered the
pre-existing non-subscription OAuth flow that worked on 0.22.4. The
account host does not serve newer models (e.g. gpt-5.4) on the responses
API, so wrapped requests began failing with unsupported-model errors
while plain Copilot and 0.22.4 kept working.
Restore 0.22.4 routing for non-subscription OAuth (generic host, still
overridable) and keep account resolution only for --subscription.
resolve_copilot_api_url now honors GITHUB_COPILOT_API_URL first, so the
override escape hatch works for every path. BYOK is unaffected.
Add a regression suite that mocks a successful user-info response, the
real-world path the prior test never exercised (it relied on the network
call failing in CI and falling back to the generic host).
* fix(copilot): route subscription + OAuth through the generic host (#610)
The 0.23.0 endpoint resolution derived the Copilot API host from
/copilot_internal/user (endpoints.api), which returns a segmented host
(e.g. api.individual.githubcopilot.com) that does not serve newer models
on the responses API and is not the host the official Copilot client
routes with (that comes from the token-exchange endpoint). --subscription
used the identical resolution, so it carried the same latent regression
as the non-subscription OAuth path.
Make Copilot host resolution override -> generic for BOTH --subscription
and the implicit OAuth path, and stop using user-info to route. Accounts
that require a dedicated host (enterprise / data residency) pin it via
GITHUB_COPILOT_API_URL. resolve_copilot_api_url no longer makes a network
call; _fetch_copilot_user_info is retained for token validation.
Update the subscription smoke tests that encoded the old account-host
assumption, and add wrap-level + unit coverage that --subscription routes
to the generic host even when user-info advertises an account host, and
that the GITHUB_COPILOT_API_URL override flows through both paths.
* docs(copilot): document generic-host routing + enterprise override (#610)
Spell out the routing contract introduced by the #610 fix so enterprise
users have a supported path. Headroom routes wrapped Copilot hosted
traffic (--subscription and OAuth) to the generic api.githubcopilot.com,
and accounts on a dedicated host (Enterprise Cloud data residency, egress
proxy) pin it via GITHUB_COPILOT_API_URL.
- copilot --help: note the generic host + GITHUB_COPILOT_API_URL override.
- TESTING-copilot-subscription.md: add "API host & Enterprise / data
residency" section; correct the stale api.*.githubcopilot.com claim; and
invite enterprise tenants who want token-exchange-based auto-detection to
open an issue.
- integration-guide.md: short hosted-host + override note in the Copilot
section.
