Expert guidance for writing XIDL (Interface Definition Language) and using the xidlc toolchain to generate multi-target APIs, SDKs, and specs. Use when defining IDL contracts, generating code (Rust, TS, Go), or mapping HTTP/REST and JSON-RPC protocols.
Enforce repository-wide final validation before finishing a change or creating a commit. Use when work is complete, when preparing the final response, or immediately before committing. This skill requires `pre-commit run -a`, `cargo clippy --all-targets --all-features -- -D warnings`, `cargo tarpaulin --manifest-path xidl-parser/Cargo.toml --packages xidl-parser --include-files "xidl-parser/src/*" --exclude-files "xidl-parser/src/typed_ast/*" --fail-under 95 --out Stdout`, and `cargo publish --workspace --dry-run --allow-dirty` to succeed from the repository root.
Draft or create git commit messages using conventional commits in a commitizen-compatible style. Use when the user asks for a commit message, wants help choosing a commit type or scope, or wants codex to commit changes with lowercase-first wording and BREAKING CHANGES footers instead of bang shorthand.
Guide code design toward simple, maintainable structure before or during implementation. Use when Codex is designing a new module, adding APIs, refactoring complex code, splitting files, reducing global state, deciding whether to introduce abstractions, or evaluating whether a feature's complexity is justified.