Dev Tools

Plot twist: Prettier — the most boring tool in your stack — just got an AI plugin. It formats your code AND suggests rename refactors based on what the variable actually does. Local LLM, no API key.

The Setup

`prettier-plugin-ai` uses a small local model (Qwen 2.5 Coder 1.5B by default) to analyse the AST and propose rename suggestions for badly-named identifiers. It runs after the format pass and writes suggestions as inline comments you can accept or ignore.

bun add -d prettier prettier-plugin-ai
# the plugin will pull the model on first run via ollama
ollama pull qwen2.5-coder:1.5b

The Money Pattern

Add it to your prettier config and behold — it's a one-liner:

{
  "semi": false,
  "singleQuote": true,
  "plugins": ["prettier-plugin-ai"],
  "ai": {
    "model": "qwen2.5-coder:1.5b",
    "mode": "suggest",
    "rules": ["rename-unclear", "rename-abbrev", "extract-magic-number"]
  }
}

Run `bun x prettier --write src/` and watch your `let x = data.map(d => d.t)` get a `// suggest: const titles = posts.map((post) => post.title)` comment above it.

The Catch

It's slow. Format-on-save goes from 20ms to 400-600ms on a typical file, which is enough to feel laggy in Cursor. Run it in `mode: suggest` rather than `apply`, and consider a pre-commit hook instead of save-on-format. Also: it occasionally suggests renaming `i` to `loopIndex` which is, you know, not it.

The Verdict

For a codebase you've inherited or a pile of vibe-coded Pipedrive scripts, this thing is a cleanup superpower. For your daily save-on-format loop, keep it off. Run it as a weekly hygiene pass and let Claude Code follow the suggestions. Try it once.