GitHub Guide: Building Reusable Agent Skills for Cross-Platform Workflows

Details

Agent skills are versioned directories centered on a SKILL.md file that capture repeatable instructions for agents to reuse across different clients.
Skills define the job, input, and output but do not grant permissions; the host environment must provide tools, credentials, and access to execute the tasks.
Project-specific configuration, such as database names and conventions, should be stored in a separate manifest file rather than hardcoded into the skill instructions to ensure portability.
A packaging script can generate client-specific files from a single source, supporting Claude Code, Cursor, and GitHub Copilot, with a check mode for CI verification.
Use human checkpoints and CI checks to verify agent work; for example, a verifier agent can return PASS, FAIL, or PARTIAL with cited evidence, blocking merges only if configured in repository rules.

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