Borrowing it
Nothing to install: this file belongs to ujjwal502/debugduck. 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/ujjwal502/debugduck/main/AGENTS.mdgit clone --depth 1 https://github.com/ujjwal502/debugduckWrote 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/instructions/ujjwal502/debugduck/agents-md)<a href="https://agentmods.dev/instructions/ujjwal502/debugduck/agents-md"><img src="https://agentmods.dev/badge/instructions/ujjwal502/debugduck/agents-md/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/instructions/ujjwal502/debugduck/agents-md"><img src="https://agentmods.dev/badge/instructions/ujjwal502/debugduck/agents-md.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 | $0.00692 | $0.00692 |
| Opus 5.5 | $0.00277 | $0.00277 |
| Sonnet 5.5 | $0.00138 | $0.00138 |
| Haiku 4.5 | $0.00069 | $0.00069 |
Grade A, and why
debugduck AGENTS.md 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 2mo 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 — 45 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Debugging
When anything is broken, failing, flaky, slow, crashing, or behaving unexpectedly — a bug
report, stack trace, failing or flaky test, regression, hang, memory leak, wrong output, a
CI-only failure, or "works on my machine" — follow the procedure in
skills/debug/SKILL.md. Read it before editing any code, then load
only the reference files under skills/debug/references/ that match the bug in front of you.
If asked to add logs, instrument a flow, or trace execution from A to Z, follow
skills/debug/references/trace-first.md.
The short version, which the full skill enforces:
- Reproduce before you diagnose. Diagnose before you fix. No repro means no feedback signal. If you genuinely can't reproduce it, say so and switch to evidence-mining — don't fix on spec.
- The bug is where the evidence points, not where it would be convenient.
- One variable at a time. Simultaneous changes destroy causality.
- To localize, trace the whole path in one pass. Instrument every checkpoint from entry to
symptom at once (numbered
CP01…CPnn), write down what each should print, run once, and find the first checkpoint where actual ≠ expected — everything upstream is then ruled out. Then stop and hand over the run command; don't guess a fix while waiting for the output. Protocol:skills/debug/references/trace-first.md. Fall back to binary search — code path, git history (git bisect run), the input, the config — when you can't re-run, the path is enormous, or logging perturbs the bug. - A root cause explains 100% of the observed evidence. Unexplained details mean you found a bug, maybe not the bug.
- Prove the fix by toggling it: revert it, watch the bug return; reapply it, watch it go. Then add a regression test and verify it fails on the pre-fix code.
- Never suppress a symptom you don't understand — no empty catch blocks, blind optional
chaining, added retries, bumped timeouts, or
# type: ignorepresented as a fix. - Label every claim
[observed],[inferred], or[assumed], and keep a hypothesis ledger (hypothesis → prediction → cheapest discriminating test → result) rather than guessing repeatedly.
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.
- 2mo ago First seen · 45 lines · 692 tokens per session scan A 2b63c44ab387
debugduck AGENTS.md is an instructions file published in the GitHub repository ujjwal502/debugduck (4 stars, last pushed 1mo ago), licensed MIT. It adds 692 tokens to every session, about $0.0028 per session on Opus 5.5. 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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