indexeddb

name	indexeddb
description	Use when user needs to store, retrieve, or persist data with no UI involved — pure data layer work

IndexedDB Skill

Design and implement a native browser IndexedDB schema with typed async helpers. No Dexie, no localForage.

Control Flow

1. Dispatch schema-designer-prompt.md to design and implement the schema
2. Dispatch reviewer-prompt.md to review it
3. If ISSUES: re-dispatch schema-designer-prompt.md with the reviewer's ISSUES list appended, then re-dispatch reviewer-prompt.md (max 3 retries)
4. If still failing: tell the user in plain English what could not be resolved
5. If APPROVED: tell the user the data store is ready and describe what was created

Migration Rules

• Every schema change increments the DB version number
• onupgradeneeded handles ALL version transitions sequentially
• Never make breaking changes to existing object stores without a migration

Error Handling Rules

All generated helpers MUST:

• Handle openDB failures (wrap in try/catch, return typed error)
• Handle transaction aborts (onerror, onabort)
• Handle quota exceeded errors
• Never silently swallow errors

Testing

• Use fake-indexeddb to mock the IndexedDB API in tests
• Co-locate test file alongside the helpers file