A lightweight workflow for small code changes that fit within one to three files and do not need a formal plan.

Use it for bug fixes, validation changes, and small configuration updates.

It keeps minor fixes focused and switches to a larger implementation process if the work grows.

fix — Skill for Claude Code and Codex by moberghr: A lightweight workflow for small code changes that fit…

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods

npx agentmods add skills/moberghr/mtk-agent-toolkit/fix

Any agent

npx skills add moberghr/mtk-agent-toolkit --skill fix

Clone the repo

git clone --depth 1 https://github.com/moberghr/mtk-agent-toolkit

Made for: Claude Code, Codex.

Or install mtk, the plugin that ships this one along with the rest of its 45 skills, 6 agents, 7 hooks, 1 MCP server.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/moberghr/mtk-agent-toolkit/fix.svg)](https://agentmods.dev/skills/moberghr/mtk-agent-toolkit/fix)

Your own site

<a href="https://agentmods.dev/skills/moberghr/mtk-agent-toolkit/fix"><img src="https://agentmods.dev/badge/skills/moberghr/mtk-agent-toolkit/fix.svg" alt="Measured on agentmods" height="20"></a>

Per session 42 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,621 The whole file, excluding the scripts and references it only reads on demand.

Security scan B 1 finding. Scan, not verified.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5	$0.00042	$0.02621
Opus 5	$0.00021	$0.01311
Sonnet 5	$0.00008	$0.00524
Haiku 4.5	$0.00004	$0.00262

Measured 4d ago against content hash ad7d9c1a8984, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

fix scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

4. Otherwise, fall back to `find ~/.claude/plugins -maxdepth 8 -name "SKILL.md" -path "*/mtk/*/context-engineering/*" -type f 2>/dev/null | sort -V | tail -1 | sed 's|/.claude/skills/context-engineering/SKILL.md||'`. If

.claude/skills/fix/SKILL.md · 188 lines

How it starts

The opening of the file, as written. The whole thing — 188 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MTK Fix — Lightweight Task Loop

MTK File Resolution

MTK skills and shared references live either in the project (local install) or the plugin cache (marketplace install). Resolve once:

If $MTK_HELPER_ROOT is set, prefix .claude/skills/ and .claude/references/ reads with it — a pinned checkout wins over every other source.
Otherwise, if $CLAUDE_PLUGIN_ROOT is set, prefix them with that.
Otherwise, if .claude/skills/context-engineering/SKILL.md exists locally → project-relative paths work as-is.
Otherwise, fall back to find ~/.claude/plugins -maxdepth 8 -name "SKILL.md" -path "*/mtk/*/context-engineering/*" -type f 2>/dev/null | sort -V | tail -1 | sed 's|/.claude/skills/context-engineering/SKILL.md||'. If empty, MTK skills are unavailable — warn the engineer and proceed with CLAUDE.md only.

Always project-relative (never prefixed): CLAUDE.md, .claude/tech-stack, .claude/rules/, tasks/, docs/, .claude/references/architecture-principles.md, .claude/references/pre-commit-review-list.md, .mtk/ (workflow state). Resolve skills and scripts from the same root: a split (skills from a local dev checkout, scripts from the plugin cache) risks version drift — anchor both the same way.

Overview

A lightweight, bounded fix loop for 1-3 file changes. Composes context-engineering, debugging-and-error-recovery, targeted TDD, and scope-guarded verification without the full feature planning overhead. Invoked by the /mtk router when the user says "fix", "bug", "broken", or similar.

Source of truth for the composed workflow:

.claude/skills/context-engineering/SKILL.md
.claude/skills/debugging-and-error-recovery/SKILL.md
.claude/skills/test-driven-development/SKILL.md when behavior changes
.claude/skills/source-driven-development/SKILL.md when framework behavior is uncertain
.claude/skills/security-and-hardening/SKILL.md when the fix touches auth, audited state, secrets, or infra
.claude/skills/tech-stack-{stack}/SKILL.md — loaded based on .claude/tech-stack

Read the full file on GitHub · 188 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

4d ago First seen · 188 lines · 42 tokens per session scan B ad7d9c1a8984

Subscribe to this mod's changes

fix is a skill published in the GitHub repository moberghr/mtk-agent-toolkit (7 stars, last pushed 10d ago), licensed MIT. It adds 42 tokens to every session and 2,621 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Debugging Planning

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

brainstorming

You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.

obra/superpowers · 37 tokens

auto-perf-optimize

Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.

microsoft/vscode · 62 tokens

chat-perf

Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.

microsoft/vscode · 51 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens

fix