Implementation Guide¶

Practical guidance for implementing The CLI Spec in your CLI tool.

Choose your language:

• Rust (clap) - with links to real, tested source code
• Go (cobra)
• Python (click)

Or jump to:

• Verifying Compliance - test your tool against the spec
• CI/CD - GitHub Actions and Makefile patterns

The part your framework cannot generate¶

Most of the schema falls out of the CLI framework you already use: command paths, flags, help text, defaults. Three things do not, and all three are required in v0.3 because they are the claims a consumer acts on:

• effects - what re-running the command does.
• cardinality - how many records a data command can return.
• output_kind - whether stdout is a document, a stream, or an artifact.

Every language guide handles these the same way: keep the declarations in one table keyed by the full command path, look them up while walking the command tree, and add a test that fails when a command has no entry. Adding a subcommand is exactly the moment the declarations go stale, and exactly the moment nobody is thinking about the schema.

Coming from v0.2? The repository ships a converter for the mechanical part, and it lists what it refuses to guess: see Migrating from v0.2.