[Bug] Plugin uninstall silently deletes unrelated settings.json keys

Bug Description

# Uninstalling a plugin/marketplace silently deletes unrelated keys from ~/.claude/settings.json ## Summary Removing a marketplace and its plugin via /plugin rewrote ~/.claude/settings.json and dropped "effortLevel": "max" — a key unrelated to plugins. The setting was lost silently: no prompt, no warning, no mention in the command output. The running session's effort level fell from max to high mid-session, and the change was only noticed later by accident. ## Environment - Claude Code, macOS (darwin 25.6.0) - Date: 2026-08-07 - Removed marketplace: darrylmorley-ollama (source: github, repo darrylmorley/ollama-plugin-cc) - Removed plugin: ollama@darrylmorley-ollama ## Steps to reproduce 1. Have "effortLevel": "max" set at the top level of ~/.claude/settings.json. 2. Register a marketplace and install a plugin from it. 3. Run /plugin and remove that marketplace and its plugin. 4. Inspect ~/.claude/settings.json. Expected: only the marketplace's own entries are removed — extraKnownMarketplaces.<name> and the matching enabledPlugins key. Actual: effortLevel is also gone. ## Evidence Two backups of settings.json were taken independently that morning, bracketing the event, plus the file's mtime: `` 08:10:43 backup A "effortLevel": "max" present (14 keys) 08:32:17 backup B "effortLevel": "max" present (14 keys) 08:41:07 settings.json write "effortLevel" ABSENT (13 keys) ` Diffing backup B against the post-event file shows exactly four removals: ` - "effortLevel": "max" - "enabledPlugins"."ollama@darrylmorley-ollama": false - "extraKnownMarketplaces"."darrylmorley-ollama": { source: github, repo: darrylmorley/ollama-plugin-cc } - one SessionStart hook entry ` The middle two are precisely what the /plugin removal was asked to do, which identifies the 08:41:07 write as /plugin's. The hook entry was removed by a separate, deliberate edit at ~08:32 (see below). That leaves effortLevel as an unrequested removal in the same write. ### Ruling out the other edit in the window The only other modification to settings.json in that window was a scripted edit at ~08:32 that removed one SessionStart hook entry via a json.load → mutate → json.dump round-trip. Replaying that exact transformation against backup B preserves the key: ` before: max after : max ` So it was not responsible. ### Not a display or session-scope artifact The key was absent from the file on disk, not merely inactive. CLAUDE_EFFORT in the running session read high. Re-running /effort restored both the session value and the on-disk key, confirming the file had genuinely lost it. ## Impact - A user-configured setting is destroyed with no warning and no undo. - The loss is silent and easy to miss — it changes model behaviour rather than producing an error. - The mechanism appears to be a whole-file rewrite that reconstructs settings.json from a known-keys schema, so **any** key the writer does not recognise is at risk, not just effortLevel. That would make the blast radius larger than this one setting. ## Suggested fix Preserve unrecognised top-level keys when rewriting settings.json — read, modify only the targeted subtrees (extraKnownMarketplaces, enabledPlugins), and write back everything else untouched. Alternatively, warn before dropping keys the writer does not own. ## Workaround Back up ~/.claude/settings.json before any /plugin install or uninstall: `bash cp ~/.claude/settings.json ~/.claude/settings.json.bak ``

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.224
• Feedback ID: d2151975-cc80-4025-b28e-cd26270748aa

Errors

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