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name: portable-safe-skills description: Create portable, safe Codex skills focused on file or I/O operations under WASIp1 constraints. Use when authoring skills that must be portable across environments and avoid unsafe assumptions about paths, preopens, or stdio.

Portable and Safe Skills

Use skill-creator

• Follow the skill-creator workflow for skill structure, naming, and packaging.
• Keep SKILL.md short and move detailed content to references/ or assets/.

Required dependency

• Use mbt-wasip1-tools for concrete CLI patterns (echo, wc, read/write) and example project structure.

Constraints to document

• WASIp1 path resolution uses longest-prefix matching against preopen names. No cwd. No fallback.
• Absolute paths only work if a preopen named / (or starting with /) exists.
• Stdio is unified: @wasi/stdio values implement both sync and async reader/writer traits.

Minimal workflow

1. Start from an assets/ example in mbt-wasip1-tools.
2. Keep logic simple and deterministic; only I/O is async.
3. Document the required wasmtime run --dir host::guest usage and expected preopens.
4. Add a README to each example with build/run commands.
5. Package the skill using the skill-creator guidelines when done.