skill-improver
- Use it when:
- A skill you're writing has quality problems and you want them fixed until it passes review, or to resume after the loop escalated.
- It does:
- Starts the code-improver plugin's background workflow, which alternates the plugin-dev skill-reviewer agent with a fixer agent round after round.
- You get:
- Fixes in your working tree, a findings ledger on disk, and a result: converged, capped but not converged, escalated or halted.
- Stops:
- On a clean review, at 5 rounds by default, when fixes stop converging, or when a change falls outside the skill's plugin folder.
- Unlike a one-time review:
- The skill-reviewer agent reviews once; this one keeps fixing and re-reviewing until a review comes back clean.
- Needs:
- Claude Code's Workflow tool, the code-improver plugin it ships in, and the plugin-dev plugin from claude-plugins-official.
Runs the code-improver plugin's improve.js workflow, which sits outside the skill folder, with the plugin-dev plugin's skill-reviewer agent: install code-improver from the trailofbits/skills marketplace and plugin-dev from claude-plugins-official. It needs Claude Code's Workflow tool.
TL;DR
From Trail of Bits' code-improver plugin. The skill finds the target skill, by path or by name among the repo's SKILL.md files, hands it to the plugin's workflow and relays the outcome; if the Workflow tool or the reviewer is missing it stops instead of improvising, because an inline loop has none of the guarantees. The ledger gives each finding a stable id and one verdict, fixed, rejected with a reason, or deferred, and is saved every round, so an escalated or interrupted run resumes without starting over. The loop escalates when blocking counts stop falling over three rounds, the same finding stays open three rounds in a row, or a finding is fixed twice; continuing means a fresh run with your decision passed in verbatim. A git-diff check after every fix round halts on any change outside the scope. Before finishing, a last pass strips loop narration, collapses version bumps to one and checks the docs against the code, and its own edits are checked too. Nothing is committed.
Summarizes the skill at e4dd0bb.
npx skills add https://github.com/trailofbits/skills --skill skill-improver skills.sh pageSource on GitHubAll skills from trailofbits/skills
- Total Downloads
- 5,400 on skills.sh, Nov 9, 2026
- Repo stars
- 8,081 trailofbits/skills
- First seen
- Feb 26, 2026 on skills.sh
Weekly values
| Week to | Installs |
|---|---|
| Sep 21 | 106 |
| Sep 28 | 107 |
| Oct 5 | 103 |
| Oct 12 | 121 |
| Oct 19 | 125 |
| Oct 26 | 153 |
| Nov 2 | 173 |
| Nov 9 | 180 |
| Category |
Find, write, vet and route to other skills. Everything for building software: planning, coding, debugging, design, frameworks, cloud, agents and skills. |
|---|---|
| Type |
A multi-step process the agent follows: interview, debug, run a TDD loop, review. |
| Effect |
Its own steps create or change files, git state or local tools. |
| Needs |
Uses Claude Code features such as hooks or background agents. Relies on the agent being able to spawn subagents. |
| Publisher |
A verified publisher on skills.sh, or the company or maintainer behind the product the skill operates. |
| Topics | |
| Stack |
SKILL.md
From trailofbits/skills at e4dd0bb. Checked daily, last changed Nov 6, 2026.
Frontmatter
name: skill-improver
description: "Runs an autonomous review-and-fix improvement loop over a Claude Code skill until a review comes back clean, with a cross-round findings ledger, escalation when fixes stop converging, and a mechanical scope guard. Reviews are performed by the plugin-dev skill-reviewer agent. Use to fix skill quality issues, iteratively refine a skill, or resume a loop after an escalation ('fix my skill', 'improve this skill until it passes review', 'skill improvement loop'). NOT for a one-time review — use the plugin-dev skill-reviewer agent directly."
argument-hint: "<SKILL_NAME_OR_PATH> [--max-rounds N]"
allowed-tools: Bash Glob Read TaskOutput TaskStop WorkflowSkill Improver
Improve a Claude Code skill by running /code-improver:improve — a dynamic workflow
that loops a reviewer and a fixer subagent until a review reports zero critical/major
findings, then strips its own residue. This entry point wires the loop to the
plugin-dev:skill-reviewer agent, so the plugin-dev plugin must be installed
(marketplace claude-plugins-official). The loop, its ledger, and its guards live in
the workflow; this skill resolves the target and relays the outcome.
Starting the loop
The user provided: $ARGUMENTS (if empty, take the target skill from the conversation).
1. Resolve the skill path
- If the input ends with
/SKILL.mdand the file exists, use its directory - If the input is a directory containing
SKILL.md, use that path - Otherwise
Glob(pattern="**/SKILL.md")and filter by skill name or path substring:- Multiple matches: ask the user to choose
- No matches: report the available skills
- Single match: proceed
2. Resolve the loop script
Resolve improve.js from this SKILL.md's installed location
to an absolute path and confirm the file exists. Its plugin directory is pluginRoot.
Use this exact plugin copy; if the file is missing, stop.
3. Invoke the workflow
Run it with the Workflow tool, {scriptPath: "<the path from step 2>", args: {...}}:
{
"target": "<resolved absolute path>",
"reviewer": {
"kind": "agent",
"name": "plugin-dev:skill-reviewer",
"notes": "The target is a Claude Code skill directory; review it as a skill (frontmatter, triggering description, progressive disclosure, referenced files)."
},
"pluginRoot": "<the plugin directory from step 2>",
"maxRounds": 5
}
maxRoundsonly if the user asked for a different cap (--max-rounds N).pluginRootis the resolved plugin directory from step 2, for the metrics collector.scope(repo-relative globs) only if the user restricted or widened what the loop may touch; by default the workflow scopes to the skill's plugin directory.decisiononly on continuation (below).
The workflow runs in the background and needs no babysitting: it reviews, fixes, re-reviews, checks scope after every fix round, and can only complete on a clean review. It never commits; all changes stay in the working tree.
If the Workflow tool is unavailable or denied, stop and say so. Do not improvise the loop inline with direct edits — the ledger, scope guard, and escalation guarantees live in the workflow, and an inline imitation has none of them (observed failure: an inline fallback "fixed" a finding by weakening the documented guarantee, exactly what the loop exists to prevent).
If the result is halted: "reviewer-unavailable", relay it and stop. The reviewer
this skill names is not installed; tell the user to install the plugin-dev plugin from
the claude-plugins-official marketplace and re-run. Do not review the skill yourself.
Do not end your turn while the loop is running. The Workflow tool returns a task id immediately; the result comes later. In an interactive session the completion notification re-invokes you — wait for it. In a non-interactive run (scripted, CI, eval) there is no later turn: stopping abandons the loop mid-round, so after launching, poll the task (TaskOutput with the returned task id, or sleep-and-recheck) until it completes, then relay the result. A session that answers "the loop is running, I'll report later" has lost the run.
Relaying the result
The workflow returns a structured result. Report it honestly — the distinctions matter:
converged: true— the last action was a review with zero critical/major findings. Report rounds used, remaining minor findings (open_minor_count), and the artifact paths (ledger_path,metrics).capped: true— the fix budget ran out and the FINAL review still found blocking issues. Say plainly: capped, NOT converged, and listopen_blocking. Do not present this as success.escalation— the loop detected it was not converging (recurring findings, non-decreasing counts, or a fix relocating a problem). Relay the escalation message and finding ids to the user: this needs a design decision, not more rounds.halted— a guard fired (scope violation, unregistered new files, a dead or unavailable reviewer, or a finalize pass whose own edits failed the check that follows it). Relay the paths inviolations/new_untracked_files, the sites infinalize_regressions, and the notes.notesalways travel with the result — surface them; they include loud warnings such as "a git repository was initialized".
Continuing after an escalation
The loop stops on escalation by design. When the user decides (e.g. "keep the blocklist
and document the limitation"), start a fresh run with the same target plus:
{ "decision": "<the user's ruling, verbatim>" }
The new run reloads the on-disk ledger, so every finding, rejection, and verdict carries over — rounds restart, re-derivation does not.
To stop a running loop, stop the workflow task (TaskStop); the ledger on disk is current to the last round and a re-run resumes from it.
What the loop enforces (so you do not have to)
- Fix verification — the next review verifies every fix; fixes to executable behavior carry pins that fail against the pre-fix code.
- Scope — a mechanical git-diff check after every fix round, and after the finalize pass, halts on any out-of-scope change; out-of-scope files git does not track are guarded by content hash, since no diff would show them; completion also requires no unregistered new files in scope.
- Report everything — reviewers report all findings with severity; filtering happens once, at the ledger verdict, and rejections are not re-litigated without new evidence.
- Finalize — before completion the loop strips narration comments, collapses version
churn to exactly one bump (in
plugin.jsonand the marketplace entry that repeats it), and runs a docs-match-code pass. Those edits land after the last review, so a check reads them: an over-eager narration strip or a false docs claim halts withfinalize-regressioninstead of passing as done.
When NOT to use
- One-time review: dispatch the
plugin-dev:skill-revieweragent directly - Quick single fixes: edit the file directly
- Non-skill targets: use the
code-improverskill with a reviewer that fits the target, orpr-improverfor a branch - Exploratory drafting: manual iteration gives more control while the shape is fluid