# Bun API Reference

> Checks local bun-types documentation before using or changing Bun runtime APIs such as Bun.$, files, spawning, argv, stdout, stderr, and string width.

- Skill: `tuyv/bun-api-reference` (Agent Skill, multi-file: 4 files)
- Install (CLI): `npx skillmds@latest add tuyv/bun-api-reference`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tuyv/bun-api-reference/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Docs & Writing
- Author: tuyv (https://skillmd.com/u/tuyv)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/tuyv/bun-api-reference

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# Bun API Reference

Use this skill when writing, reviewing, or debugging code that calls Bun runtime APIs.

## Local References

Start with:

```text
node_modules/bun-types/README.md
node_modules/bun-types/docs/
```

Search local docs and types with `rg`:

```sh
rg "Bun\\.\\$|Bun\\.file|Bun\\.write|Bun\\.spawn" node_modules/bun-types
rg "stringWidth|deepEquals|stdout|stderr" node_modules/bun-types
```

Prefer the local `bun-types` documentation over memory when checking API signatures, return types, options, and subtle behavior.

## Common APIs To Verify

- `Bun.$`
- `Bun.file()`
- `Bun.write()`
- `Bun.spawn()`
- `Bun.argv`
- `Bun.deepEquals()`
- `Bun.file().writer()`
- `Bun.stdout`
- `Bun.stderr`
- `Bun.stringWidth()`

If the docs are missing or `node_modules` is unavailable, inspect existing local usage with `rg` and state the gap before relying on fallback knowledge.