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 JakubMikolajek/codex-skills-collection --skill debug-tracegit clone --depth 1 https://github.com/JakubMikolajek/codex-skills-collectionWrote 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/jakubmikolajek/codex-skills-collection/debug-trace)<a href="https://agentmods.dev/skills/jakubmikolajek/codex-skills-collection/debug-trace"><img src="https://agentmods.dev/badge/skills/jakubmikolajek/codex-skills-collection/debug-trace/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/jakubmikolajek/codex-skills-collection/debug-trace"><img src="https://agentmods.dev/badge/skills/jakubmikolajek/codex-skills-collection/debug-trace.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 | $0.00036 | $0.01279 |
| Opus 5 | $0.00018 | $0.00639 |
| Sonnet 5 | $0.00007 | $0.00256 |
| Haiku 4.5 | $0.00004 | $0.00128 |
Grade A, and why
debug-trace 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 9d 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.
How it starts
The opening of the file, as written. The whole thing — 142 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Debug Trace
This skill enforces structured root cause analysis before any fix is written. It prevents surface-level patches by requiring a complete Debug Report before code changes. No fix without a trace.
When to Use
- Task contains: "bug", "error", "fix", "broken", "not working", "failing", "crash", "exception", "wrong output"
- A test is failing and the cause is not immediately obvious
- A previous fix did not resolve the issue (regression or misdiagnosis)
- Behavior differs between environments (local vs CI, iOS vs Android, dev vs prod)
When NOT to Use
- Task is planned feature implementation with no existing bug
- Task is a refactor where the current behavior is correct but the code needs restructuring
- User explicitly provides the root cause and only needs help writing the fix
Core Principles
No Fix Without a Debug Report
This is non-negotiable. Writing code before completing analysis produces patches, not fixes. The Debug Report must be completed before any fix code is written.
Mandatory Pre-Fix Analysis
Follow these steps in order. Do not skip steps.
Step 1 — Reproduce
Confirm the exact condition that triggers the bug: input, state, environment, user action sequence. If it cannot be reproduced, do not proceed to Step 2 — see "Cannot Reproduce" below.
Construct the tightest feedback loop available, in this order:
- Failing test at the right seam
- HTTP script against a running dev server
- CLI invocation with a fixture, diffing output
- Headless browser automation
- Captured trace replay
- Minimal harness
- Property/fuzz loop with many random inputs
- Bisection harness between known-good and known-bad states
- Differential testing of old versus new behavior
- Human-in-the-loop bash script — last resort only
Target a deterministic loop under 2 seconds; for flaky bugs, target a 50%+ reproduction rate before Step 2.
Step 2 — Isolate
Identify the smallest code unit responsible: function, component, query, middleware. Narrow by removing surrounding code mentally or via test.
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.
- 9d ago First seen · 142 lines · 36 tokens per session scan A 26ddcad4060e
debug-trace is a skill published in the GitHub repository JakubMikolajek/codex-skills-collection (5 stars, last pushed 3d ago), licensed MIT. It adds 36 tokens to every session and 1,279 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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