gap-trap

Turns vibe coding into high quality code. Complements SDD if you are using it (think of it as the inner loop within)

The problem

An agent writes most of your code. It is fast, so you stop reading every diff. Quality drifts, and you find out when something breaks.

The drift looks the same in every codebase. The agent writes a helper that already exists. It crosses a layer boundary because the shortcut compiled. It writes a test that asserts the code ran, not that it did the right thing. It follows a rule in your instructions file for a week and then forgets it.

Nothing stops any of this. The rules are text, and the only thing that reads them is the agent that breaks them.

What gap-trap does

Run it once in a repository. It reads the code, writes the rules that fit that codebase, and adds a gate for each rule. A gate is a check that fails the commit or the CI run when the rule is broken. The agent cannot skip a gate.

It sets up four things:

It also installs slop-mop, a sibling skill, so the agent's docs, commit messages, and PR bodies read like a person wrote them. A harness loads its skills when the session starts, so slop-mop applies from the session after the one that installs it.

Works with any language. Node and Python repos get gates inside their test suite; everything else (Go, Rust, Java, Ruby, .NET, PHP, Swift, C++) gets shell versions that need only git, grep, awk, and your test command.

IMPORTANT: Validate the rules/contracts that are generated. This is where it is important to review thoroughly so you start with a strong foundation.

Install

With the skills CLI:

npx skills add pliablepixels/gap-trap

Or by hand. Claude Code reads ~/.claude/skills, Codex reads ~/.agents/skills:

git clone https://github.com/pliablepixels/gap-trap.git
mkdir -p ~/.claude/skills            # Codex: mkdir -p ~/.agents/skills
cp -r gap-trap/gap-trap ~/.claude/skills/

The skill runs on the top coding model of the harness (Opus or better in Claude Code, the frontier coding model at high reasoning in Codex) and stops on anything smaller. Choosing the wrong contracts costs every later session.

Update

Every push to main is a new version. With the skills CLI:

npx skills update gap-trap

For a hand install, pull the clone and replace the copy, so files removed upstream do not linger:

git -C gap-trap pull
rm -rf ~/.claude/skills/gap-trap     # Codex: ~/.agents/skills/gap-trap
cp -r gap-trap/gap-trap ~/.claude/skills/

A repository you already set up keeps the files setup wrote. Updating the skill changes what the next setup or refine run does.

Run

In the repository you want to set up:

/gap-trap setup

Codex invokes the same skill as $gap-trap setup.