New AI projects on Hugging Face or GitHub, May 29 2026. One repo taught its agent to fail over from Claude to Gemini mid-conversation.

Neither platform publishes a dated release list. Models, datasets, papers, and repositories surface continuously, ordered by a rolling trending score rather than by calendar date. The closest thing to a true daily record is a tagged release or a commit log, where each change carries an author, a message, and a timestamp. The record that genuinely carries 2026-05-29 and is worth reading: the open-source macOS agent Fazm pushed 74 commits across 30 files and cut three patch releases (v2.9.53 at 10:41, v2.9.54 at 14:30, v2.9.55 at 18:08 Pacific). Most of the evening went into one feature that is unusual for a Claude Code wrapper: a transparent failover from Claude to Gemini. When the bundled Claude key dies or hits a rate limit, the agent quietly continues the same conversation on Gemini instead of showing an error.

It is a cross-vendor fallback that keeps a chat alive when the built-in (shared) Claude key cannot serve a turn. The logic lives in ChatProvider.swift behind a session flag named builtinClaudeKeyDead and a computed property geminiFallbackModelId. When a turn throws because the built-in key authentication failed, the app refetches the key from the backend /v1/keys endpoint once, restarts the bridge if the key actually rotated, and replays the message silently. If the refetch returns the same or an empty key, the key is treated as genuinely dead: the app sets builtinClaudeKeyDead, switches the selected model to a Gemini id, re-arms the pending message, and clears errorMessage so nothing surfaces to the user. The combined change is roughly +154 / -17 lines in ChatProvider.swift across commits 947a5eb3, f336947c, ecfdbd1b, 9ed461f6, and 647ee8bf. It shipped to users the next morning as v2.9.56.

Because retrying Claude with a dead or throttled built-in key reproduces the same failure every turn. The app already does the cheap recovery first: it refetches the key once per 30 seconds (a cooldown named builtinKeyRefetchCooldown) in case the backend rotated it, and restarts the bridge so the new ANTHROPIC_API_KEY lands in the subprocess. Gemini is the path taken only after that recovery fails, or while the rate limit is still in effect. Gemini queries do not bill the Anthropic key (they run on Fazm's bundled Gemini access), so the user is not blocked behind a cap that has not reset. The design goal stated in the source comments is to avoid dead-ending on a retry-only error.

It is deliberately silent. The branches that route to Gemini all set errorMessage = nil and re-arm the pending message through a flag named retryAfterBuiltinKeyRefetch, so the same prompt replays on Gemini and the assistant answer just appears. There is no modal, no error bubble, and no manual model switch required. The model picker reflects the new selection, but the conversation continues from the next message as if nothing happened. The trade-off the author accepts is that the user is now talking to a different model family; the alternative was a hard stop.

The geminiFallbackModelId property picks, in order: gemini-pro-latest if the picker probe has advertised it, then gemini-flash-latest, then any advertised Gemini id, then the canonical gemini-pro-latest alias the bridge accepts even before the probe populates. The comment in the source says it prefers Pro because it is the smartest available, so a silent downgrade in vendor is not also a silent downgrade in capability when it can be avoided. Routing in the bridge is model-id-based, so the alias resolves even if the probe has not finished listing the user's available Gemini variants yet.

They share the Gemini reroute but differ in whether Claude is allowed to recover. The dead-key path (builtinKeyInvalid) sets builtinClaudeKeyDead = true, which makes later turns route hard-coded Claude sends to Gemini too, so the app does not waste a doomed Claude attempt per turn for the rest of the session. The rate-limit path (credit/rate limit exhausted, isRateLimitExhaustion true) deliberately does NOT set builtinClaudeKeyDead, because the limit resets: it switches to Gemini for the current turn and lets Claude auto-recover on a later turn. One is a session-long redirect; the other is a per-turn rescue. Both clear errorMessage and replay silently, and both only fire if a Gemini model is actually available to fall back to.

Three things stand out in the same log. First, a custom API endpoint mode for the ACP bridge (commits around 16:40), so a turn can route through a corporate proxy, GitHub Copilot, or any Anthropic-compatible gateway, with the bundled key and built-in credits explicitly disabled when a custom endpoint is set. Second, an in-app RoutineScheduler (commit 887dbcbb, a 175-line new file plus AppDelegate wiring) that fires recurring routines on time while the app is open, fixing scheduled routines that never ran. Third, founder-chat attachments: paste, drag-and-drop, or attach a file, backed by GCS signed URLs (commits d463f5ee through 63bd6a3e). v2.9.55 also fixed Gemini occasionally returning an empty reply by rescuing text the engine streamed under a mismatched session id, the routing decision tested in decideGeminiRoute.

Three artifacts, in order. Open the project's CHANGELOG.json or CHANGELOG.md at the root and read the entries dated 2026-05-29. Open the commit log with `git log --since=2026-05-29 --until=2026-05-30 --no-merges` and read the messages, ignoring the release-changelog commits. Then pick one commit whose subject sounds load-bearing (here, 'Add Gemini fallback when built-in Claude key is dead') and run `git show <hash>` to read the diff and the comment the author left for future readers. The trending page tells you what existed at the end of the day; the diff tells you what someone decided, and why.

github.com/mediar-ai/fazm is the public repo. The failover lives in Desktop/Sources/Providers/ChatProvider.swift: the builtinClaudeKeyDead flag and geminiFallbackModelId property near the top of the class, the dead-key and rate-limit branches in the sendMessage error handler, and the send-time redirect that rewrites a hard-coded Claude model id to Gemini while the key is dead. The empty-reply routing logic is in acp-bridge/src/gemini-provider.ts (decideGeminiRoute) with tests in acp-bridge/test/gemini-route.test.mjs. Release notes are in CHANGELOG.json at the repo root.