If you’ve opened Antigravity one day and found your chat history empty – you’re not alone, and your data is almost certainly still there.
I lost 26 chat sessions after an update. The sidebar showed almost nothing. I spent hours trying every workaround I could find: reopening workspaces, tapping through Agent Manager, editing state.vscdb directly. Nothing worked.
Eventually I figured out what’s actually happening: the .pb files (your actual conversation data) are still sitting on disk, perfectly intact. They’re just missing from trajectorySummaries – the internal index that tells the UI what to display. Antigravity doesn’t scan the conversations/ directory on startup. If a .pb isn’t in the index, it’s invisible.
The fix is what I’m calling “.pb injection”: you create a dummy chat (which gets registered in the index), then overwrite its .pb file with the missing conversation’s .pb. On restart, Antigravity reads the real content through the dummy’s index entry. It’s simple, reliable, and I recovered all 26 sessions this way.
But there’s a cautionary tale baked into this guide. During an earlier automated attempt, an AI agent identified dummy chats by file size instead of birth time. Three real conversations – short ones under 200KB – got misidentified and permanently overwritten. No Time Machine backup. Gone forever. That mistake is documented in detail because I don’t want anyone else to repeat it.
The complete guide covers:
- Root cause analysis – why chats disappear and how the index/file desync works
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- Step-by-step .pb injection – the full 6-phase procedure with batch processing
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- Birth-time identification – the safe way to distinguish dummies from real chats (macOS, Windows, Linux)
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- Safety protocols – what NOT to do, based on real data loss
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- Post-recovery behavior – what works and what doesn’t (title updates, timestamps, agent summaries)
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- AI agent instructions – a copy-paste prompt for using this guide with Antigravity’s built-in agent
Link: GitHub - keisksw/antigravity-chat-recovery: Complete guide for recovering lost chat history in Antigravity IDE using the .pb injection method · GitHub
- AI agent instructions – a copy-paste prompt for using this guide with Antigravity’s built-in agent
If you’re staring at an empty chat sidebar right now – take a breath. Your conversations are probably fine. Back them up first (cp -a ~/.gemini/antigravity/conversations/ ~/Desktop/conversations_backup/), then follow the guide.
A note to the Antigravity team (@anthropic-eng, @google-devs):
This workaround exists because Antigravity doesn’t re-scan the conversations/ directory on startup. A filesystem scan that reconciles .pb files against trajectorySummaries on launch would prevent this entire class of bug – and it should be a relatively contained fix.
Additionally, after .pb injection, trajectorySummaries doesn’t regenerate conversation metadata (titles, timestamps, summaries). If there’s an internal API or developer flag to trigger a per-UUID summary refresh, exposing that would make recovery much cleaner.
This bug has been reported across versions 1.18.x through 1.20.x and affects users on all platforms. The data architecture is sound – conversations survive because .pb files are self-contained. The gap is purely in the index lifecycle. I’d be happy to provide detailed reproduction steps or collaborate on testing a fix.
I’d also love to hear from the community – if anyone has figured out how to force trajectorySummaries regeneration after recovery, please share. The content fully restored, but sidebar titles and timestamps stay frozen – it’s the one thing I haven’t been able to solve.