The pre-flight auth check in resolveModelOverrideWithAuthFallback called
getApiKey without a session id. For providers with session-sticky OAuth
credentials, this returned undefined even though the credential was
usable once the subagent session started, causing the auth fallback to
silently replace the configured model with the parent's (#5325).
The subagent's id is now forwarded as the session id so session-sticky
credentials resolve during the pre-flight check. Genuinely broken auth
(stale OAuth, revoked tokens) still falls back as before.
Also propagate model resolution warnings through resolveModelOverride
and log them in the executor so users see why a pattern didn't match.
- Centralized catalog and registry handling on `ModelSpec` and `buildModel`, resolving compatibility at model build time.
- Removed runtime compatibility detectors and switched provider request flows to direct `model.compat` reads.
- Added compat fields (`supportsReasoningParams`, `alwaysSendMaxTokens`, `strictResponsesPairing`, `whenThinking`).
- Persisted explicit compatibility overrides through `compatConfig` in discovery and cache merge paths.
Reporter screenshot showed a parent session on DeepSeek V4 Pro dispatching
a task subagent that resolved to `qwen3.6-plus-free` — an opencode-zen
model the user had no working credentials for. The dispatch hit a
provider that could not serve the model and surfaced a confusing API
rejection instead of using the parent's already-authenticated model.
Adds `resolveModelOverrideWithAuthFallback`, an auth-aware wrapper
around `resolveModelOverride` that checks the resolved subagent model's
credentials via `modelRegistry.getApiKey` + `isAuthenticated` and
falls back to the parent session's active model pattern when the
primary has no working auth. The parent's active model is plumbed
through `ExecutorOptions.parentActiveModelPattern` from `TaskTool`
into `runSubprocess`. If neither has working auth (or they resolve to
the same model), the primary resolution is preserved so the existing
error path still surfaces a meaningful failure downstream.
Fixes#985
can1357