command-authoring

To write cross-CLI slash commands, you author a single canonical `.claude/commands/<name>.md` source with YAML frontmatter and a neutral body. This standard generates deterministic Codex and Gemini artifacts while preserving the core prompt logic.

The slash command body must stay within a strict line cap, specifically under 150 lines, to avoid prompt-context crowding. Enforcing this body constraint ensures safe execution and prevents the command from crowding out the user's intent.

Yes, cross-CLI command frontmatter requires `name` and `description` semantics, including listing-budget constraints. Optional fields like `argument-hint` and `allowed-tools` are also supported to define safe command behavior.

You should use a slash command for direct, neutral prompt actions and use an agent or skill for complex logic. The command-authoring standard clarifies this separation to prevent duplicated logic and broken behavior across CLI platforms.

Yes, the command-authoring standard supports native-primitive carve-outs and variant overlay slot semantics. These features allow you to maintain cross-CLI hygiene while accommodating specific platform behaviors within your deterministic command emissions.

Slash command prompts break across CLIs due to inconsistent phrasing and lack of cross-CLI hygiene. Applying a single-source authoring standard with neutral phrasing and sync-manifest wiring prevents this drift and ensures deterministic behavior.