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.
npx skills add manhvann/codexkit --skill debuggit clone --depth 1 https://github.com/manhvann/codexkitWrote 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.
[](https://agentmods.dev/skills/manhvann/codexkit/debug)<a href="https://agentmods.dev/skills/manhvann/codexkit/debug"><img src="https://agentmods.dev/badge/skills/manhvann/codexkit/debug/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/manhvann/codexkit/debug"><img src="https://agentmods.dev/badge/skills/manhvann/codexkit/debug.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 5.1 | $0.00047 | $0.01138 |
| Opus 5.5 | $0.00019 | $0.00455 |
| Sonnet 5.5 | $0.00009 | $0.00228 |
| Haiku 4.5 | $0.00005 | $0.00114 |
Grade A, and why
ck:debug scanned grade A with 0 findings 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 1mo 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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
This is a copy
86% identical to vc-debug — 26 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Debugging & System Investigation
Comprehensive framework combining systematic debugging, root cause tracing, defense-in-depth validation, verification protocols, and system-level investigation (logs, CI/CD, databases, performance).
Core Principle
NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST
Random fixes waste time and create new bugs. Find root cause, fix at source, validate at every layer, verify before claiming success.
When to Use
Code-level: Test failures, bugs, unexpected behavior, build failures, integration problems System-level: Server errors, CI/CD pipeline failures, performance degradation, database issues, log analysis Always: Before claiming work complete
Techniques
1. Systematic Debugging (references/systematic-debugging.md)
Four-phase framework: Root Cause Investigation → Pattern Analysis → Hypothesis Testing → Implementation. Complete each phase before proceeding. No fixes without Phase 1.
Load when: Any bug/issue requiring investigation and fix
2. Root Cause Tracing (references/root-cause-tracing.md)
Trace bugs backward through call stack to find original trigger. Fix at source, not symptom. Includes scripts/find-polluter.sh for bisecting test pollution.
Load when: Error deep in call stack, unclear where invalid data originated
3. Defense-in-Depth (references/defense-in-depth.md)
Validate at every layer: Entry validation → Business logic → Environment guards → Debug instrumentation
Load when: After finding root cause, need comprehensive validation
4. Verification (references/verification.md)
Iron law: NO COMPLETION CLAIMS WITHOUT FRESH VERIFICATION EVIDENCE. Run command. Read output. Then claim result.
Load when: About to claim work complete, fixed, or passing
5. Investigation Methodology (references/investigation-methodology.md)
Five-step structured investigation for system-level issues: Initial Assessment → Data Collection → Analysis → Root Cause ID → Solution Development
What ships with it
12 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/defense-in-depth.md 3.6 KB
- references/frontend-verification.md 3.6 KB
- references/investigation-methodology.md 4.0 KB
- references/log-and-ci-analysis.md 3.4 KB
- references/performance-diagnostics.md 3.8 KB
- references/reporting-standards.md 2.6 KB
- references/root-cause-tracing.md 3.3 KB
- references/systematic-debugging.md 4.1 KB
- references/task-management-debugging.md 5.4 KB
- references/verification.md 3.3 KB
- scripts/find-polluter.sh 1.5 KB runs code
- scripts/find-polluter.test.md 2.1 KB
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.
- 1mo ago First seen · 122 lines · 47 tokens per session scan A 9aec9cb6fead
ck:debug is a skill published in the GitHub repository manhvann/codexkit (89 stars, last pushed 1mo ago), licensed MIT. It adds 47 tokens to every session and 1,138 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 86% identical to vc-debug, differing in 26 lines, and is treated as a copy.
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