In updateChannel (channel-manager.ts), when a channel's provider is switched to openai or custom, the effectiveApiFormat falls back via input.apiFormat ?? existing.apiFormat — but existing.apiFormat was undefined for the previous non-openai provider, leaving apiFormat silently unset after the transition. The caller would need to always supply an explicit apiFormat when changing provider type, which isn't enforced anywhere visible in this diff.

The testCustomOpenAICompatible function returns resolvedBaseUrl in the ChannelTestResult, which is a useful signal, but nothing in the diff shows the test result's resolvedBaseUrl being persisted back to the channel config. If the user runs a connectivity test and /v1 gets auto-detected, the channel's stored baseUrl won't actually be updated — so subsequent requests from agent-orchestrator.ts would still use whatever the user originally typed, relying on normalizeOpenAIBaseUrl being called at runtime rather than at configuration time.

Also worth noting: the ensureV1: boolean = false parameter added to testOpenAICompatible is passed as true only for provider === 'openai', meaning providers like deepseek and moonshot still use normalizeBaseUrl instead of normalizeOpenAIBaseUrl. If those providers also serve under /v1, this inconsistency could silently affect test reliability for those channels.