Antigravity gemeni 3.8 deleted every brain file without authorization

Google Antigravity
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1

Today I started getting persistent failed to fetch from conversations being too long, gemeni said it had identified two large brain files and that deleting them would solve the issue. I asked it to first make copies of them locally. After I asked it to delete the two problem files. I then proceeded to without asking me, delete every brain file. The persistent fail to fetch from large files ate every token I had across two accounts. I am completely stuck on half a dozen projects that now have 0 context.

2

I’ve never trusted that a conversation would remain intact. I always make sure that new actionable items turn into tickets, and new plans turn into files within my repo that are committed and pushed.

3

It’s true 3.8 flash is really doing unnecessary work and it reads a lot of code files before making a update eating the quota quickly with 1 or 2 prompts, but it’s a powerful model.

I prefer the 3.6 flash as the balanced and quick model in antigravity. I even wrote a post about 3.8 flash: Gemini 3.6 flash is better than 3.7 and 3.8

4

Hi @Sean_Duffy ,

To resolve, could you please follow the below steps:

  1. Recover Your Chat History & Text Artifacts (conversations/*.db):

    • Your conversation databases are stored separately from brain/ inside ~/.gemini/antigravity/conversations/ (%USERPROFILE%\.gemini\antigravity\conversations\ on Windows). While deleting brain/ removes standalone workspace artifacts/images that weren’t in Git, the .db files retain your full chat transcripts and the write_to_file step payloads (so text plans like task.md or implementation_plan.md can still be extracted), and migration snapshots are kept in ~/.gemini/antigravity-backup/.

  2. Update to Antigravity 2.0 v2.15.1 / Antigravity IDE v2.5.5 (Download | Changelog):

    • Version v2.15.0 / v2.15.1 fixes the duplicate-permission bloat bug that caused long conversations to fail with "failed to fetch" errors, so you never need to manually delete brain/ files to fix fetch errors.

  3. Enforce OS Sandbox & Path-Level Deny Rules:

    • In Settings → General → Global Permissions, keep your preset on Default (which enforces OS-level syscall sandboxing against both shell commands and scripts) and add both write_file(~/.gemini/antigravity/brain) and command(rm -rf) / command(Remove-Item) to your Deny List (Permissions Docs).
    • To avoid the heavy file-reading token drain on Gemini 3.8 Flash, switch the model selector to Gemini 3.6 Flash and commit core project plans to GEMINI.md / AGENTS.md in Git.

Please check if your .db files are still present in ~/.gemini/antigravity/conversations/ — if so, could you please let us know to help you further.