# X07 Language Guide

> Canonical X07 language + stdlib reference (mirrors `x07 guide` output) for end-user skill packs. Use when this capability is needed.

- Skill: `tomevault-io/x07-language-guide` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add tomevault-io/x07-language-guide`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/x07-language-guide/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: tomevault-io (https://skillmd.com/u/tomevault-io)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/tomevault-io/x07-language-guide

---


# x07-language-guide

This skill provides the canonical language and stdlib reference generated by `x07 guide`.

## Canonical commands

- `x07 guide`: print the full language + stdlib guide.
- `x07 doc <id>`: look up a single symbol (builtin, stdlib function, diagnostic code, schema id).

## Key concepts to align on

- Loops: use `for` for counted loops and `while` for scanning/open-ended loops.
- Error propagation:
  - typed results (`result_i32`, `result_bytes`) use `try`
  - doc envelopes use `try_doc` (and return `bytes`)
- Version + compat:
  - prefer `project.compat` in `x07.json` as the stable default
  - use `x07 migrate --check/--write --to 0.5` for mechanical rewrites when upgrading older code

See `references/language-guide.md`.

---
> Converted and distributed by [TomeVault](https://tomevault.io/claim/x07lang) — claim your Tome and manage your conversions.
<!-- tomevault:4.0:skill_md:2026-04-13 -->