Installation

Human is a plain-text format. You can write .hmn files in any editor without installing anything. But the tooling makes it better.

CLI (hmn)

The hmn binary validates, compiles, and formats .hmn files. Install from source:

cargo install --path human/cli

Verify:

hmn --help

usage: hmn <command> [flags] file...

commands:
  validate   check .hmn files for errors
  compile    compile .hmn to prompt, json, yaml, toml, txt, hmn
  fmt        normalize .hmn source formatting

Homebrew and npm packages are planned but not yet available.

VS Code Extension

The vscode-human extension provides syntax highlighting and on-save diagnostics for .hmn files.

Install from VSIX:

1. Open VS Code or Cursor
2. Open the Command Palette (Cmd+Shift+P)
3. Run Extensions: Install from VSIX…
4. Select the human-language-0.1.0.vsix file from the vscode-human/ directory

The extension runs hmn validate on save and reports errors inline.

No Install Required

You don’t need the CLI or extension to use Human. It’s a plain-text configuration format. You can write it in Notepad, Vim, or on paper.

AGENT helper

CONSTRAINTS rules
  NEVER lie
  MUST help

Save it as a .hmn file. That’s a valid Human configuration.

The CLI adds validation (hmn validate), compilation to various output formats (hmn compile), and source formatting (hmn fmt). The VS Code extension adds syntax highlighting and error reporting. But the format stands on its own.

Platform Support

Human (the specification) works everywhere text works.

The hmn CLI currently builds from source via Cargo on:

• macOS (arm64, x86_64)
• Linux (arm64, x86_64)
• Windows (x86_64)

Pre-built binaries are planned.

Tree-sitter Grammar

A Tree-sitter grammar is available in tree-sitter-human/ for editor plugin authors who want to build integrations beyond VS Code. It handles indentation-sensitive parsing via an external scanner and provides highlights.scm queries for syntax coloring.

Getting Updates

Human is experimental. Watch the GitHub for updates: github.com/human-language

Questions

Q: Can I use Human without the CLI? A: Yes. It’s just text. Write it, share it, version control it.

Q: When will brew/npm packages be ready? A: Follow the repo for updates.

Q: What if the spec changes? A: The five constraint levels are permanent. Everything else might evolve.

Q: Can I contribute? A: Yes. The spec and implementation are open source.