Agent skill · software engineering · github
harness-engineering
Adopt repository-level harness engineering for coding agents. Use when a user wants to prevent repeated AI coding-agent mistakes by turning failures into durable instructions, drift checks, regression tests, failure memory, and adoption reports tailored to the target repository.
Why this skill is useful
Adds specific repository-level harness engineering practices and scripts that improve the reliability of coding agents, which are not commonly found in public documentation.
What it needs
About 5k tokens when loaded. Last updated 2026-08-07. 37,534 stars on the source repository.
What this skill does
Harness Engineering Harness engineering turns repeated coding-agent mistakes into durable repository artifacts: Use this skill when the user asks to: make a repository more reliable for GitHub Copilot or other coding agents add durable agent instructions, repository rules, or guardrails prevent repeated AI coding-agent mistakes record known failure paths and the checks that prevent recurrence add lightweight drift checks for project rules review, refresh, or update an existing agent harness Do not use this skill for ordinary feature implementation unless the user asks to improve the repository's agent operating environment. Core Principles Treat the target repository as the source of truth. Inspect before editing. Preserve the existing stack, package manager, CI, docs, naming, and architecture. Add the smallest useful harness. Prefer updating existing files over adding duplicate guidance. Make important rules enforceable where practical through tests, linters, type checks, CI, pre-commit hooks, or drift scripts. Use manual review points only when automation would be brittle or misleading. Record high-risk failures that should not recur, and name the check or review point that catches recurrence. Do not copy generic templates blindly. Adapt every artifact to real evidence in the target repository. Discovery Before proposing or making harness changes, inspect the repository for existing rules and evidence. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills github/harness-engineering