Borrowing it
Nothing to install: this file belongs to mtnyilmaz/agents. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/mtnyilmaz/agents/main/.agents/skills/methodology-debugging/SKILL.mdgit clone --depth 1 https://github.com/mtnyilmaz/agentsWrote 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/mtnyilmaz/agents/methodology-debugging)<a href="https://agentmods.dev/skills/mtnyilmaz/agents/methodology-debugging"><img src="https://agentmods.dev/badge/skills/mtnyilmaz/agents/methodology-debugging/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/mtnyilmaz/agents/methodology-debugging"><img src="https://agentmods.dev/badge/skills/mtnyilmaz/agents/methodology-debugging.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 | $0.00045 | $0.02380 |
| Opus 5.5 | $0.00018 | $0.00952 |
| Sonnet 5.5 | $0.00009 | $0.00476 |
| Haiku 4.5 | $0.00005 | $0.00238 |
Grade A, and why
debugging-and-error-recovery 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
95% identical to debugging-and-error-recovery — 10 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 — 301 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Debugging and Error Recovery
Overview
Systematic debugging with structured triage. When something breaks, stop adding features, preserve evidence, and follow a structured process to find and fix the root cause. Guessing wastes time. The triage checklist works for test failures, build errors, runtime bugs, and production incidents.
When to Use
- Tests fail after a code change
- The build breaks
- Runtime behavior doesn't match expectations
- A bug report arrives
- An error appears in logs or console
- Something worked before and stopped working
The Stop-the-Line Rule
When anything unexpected happens:
1. STOP adding features or making changes
2. PRESERVE evidence (error output, logs, repro steps)
3. DIAGNOSE using the triage checklist
4. FIX the root cause
5. GUARD against recurrence
6. RESUME only after verification passes
Never push past a failing test or broken build to work on the next feature. Errors compound. A bug in Step 3 that goes unfixed makes Steps 4-10 wrong.
The Triage Checklist
Work through these steps in order. Do not skip steps.
Step 1: Reproduce
Make the failure happen reliably. If you can't reproduce it, you can't fix it with confidence.
Can you reproduce the failure?
├── YES → Proceed to Step 2
└── NO
├── Gather more context (logs, environment details)
├── Try reproducing in a minimal environment
└── If truly non-reproducible, document conditions and monitor
When a bug is non-reproducible:
Cannot reproduce on demand:
├── Timing-dependent?
│ ├── Add timestamps to logs around the suspected area
│ ├── Try with artificial delays (setTimeout, sleep) to widen race windows
│ └── Run under load or concurrency to increase collision probability
├── Environment-dependent?
│ ├── Compare Node/browser versions, OS, environment variables
│ ├── Check for differences in data (empty vs populated database)
│ └── Try reproducing in CI where the environment is clean
├── State-dependent?
│ ├── Check for leaked state between tests or requests
│ ├── Look for global variables, singletons, or shared caches
│ └── Run the failing scenario in isolation vs after other operations
└── Truly random?
├── Add defensive logging at the suspected location
├── Set up an alert for the specific error signature
└── Document the conditions observed and revisit when it recurs
What ships with it
1 file 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.
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 · 301 lines · 45 tokens per session scan A ef67945f5f06
debugging-and-error-recovery is a skill published in the GitHub repository mtnyilmaz/agents (6 stars, last pushed 5mo ago), licensed MIT. It adds 45 tokens to every session and 2,380 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 95% identical to debugging-and-error-recovery, differing in 10 lines, and is treated as a copy.
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