bug-reproducer

bug-reproducer is a skill for Claude Code, Codex from AnastasiyaW/codex-claude-code-config. It costs 147 tokens per session (3,280 once invoked), scanned A, original, MIT.

A debugging workflow that investigates suspected software bugs and proves or rejects them with focused regression tests. A regression test checks that a reported failure stays fixed after a change.

In plain words
What is it for?
Use it to find likely bugs, reproduce a reported failure, identify its cause, and support a proposed fix with red-to-green test evidence.
Why use it?
It separates confirmed bugs from guesses and creates a small reproducible example from reports, stack traces, screenshots, or failing behavior. Inspection-only requests do not automatically authorize changing production code.

Skill for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present. Also seen: mentions Codex.

Part of the claude-code-config plugin — 57 skills, 8 agents shipped together

Good fit Use it to find likely bugs, reproduce a reported failure, identify its cause, and support a proposed fix with red-to-green test evidence.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/anastasiyaw/codex-claude-code-config/bug-reproducer
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.

Any agent
npx skills add AnastasiyaW/codex-claude-code-config --skill bug-reproducer
Clone the repo
git clone --depth 1 https://github.com/AnastasiyaW/codex-claude-code-config

Made for: Claude Code, Codex.

Or install claude-code-config, the plugin that ships this one along with the rest of its 57 skills, 8 agents.

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.

agentmods badge for bug-reproducer

README.md
[![agentmods](https://agentmods.dev/badge/skills/anastasiyaw/codex-claude-code-config/bug-reproducer/github.svg)](https://agentmods.dev/skills/anastasiyaw/codex-claude-code-config/bug-reproducer)
Your own site
<a href="https://agentmods.dev/skills/anastasiyaw/codex-claude-code-config/bug-reproducer"><img src="https://agentmods.dev/badge/skills/anastasiyaw/codex-claude-code-config/bug-reproducer/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.

agentmods 80×15 button for bug-reproducer

Your own site · 80×15
<a href="https://agentmods.dev/skills/anastasiyaw/codex-claude-code-config/bug-reproducer"><img src="https://agentmods.dev/badge/skills/anastasiyaw/codex-claude-code-config/bug-reproducer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 147 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,280 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 12
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
How audits are shown
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00147 $0.03280
Opus 5 $0.00073 $0.01640
Sonnet 5 $0.00029 $0.00656
Haiku 4.5 $0.00015 $0.00328

Measured yesterday against content hash 11792325ceef, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

bug-reproducer 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 yesterday.

The scan reads SKILL.md. This mod also ships 4 executable files (scripts/capture_command.py, scripts/compare_evidence.py, scripts/generate_report.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

skills/development/bug-reproducer/SKILL.md · 241 lines

How it starts

The opening of the file, as written. The whole thing — 241 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Bug Reproducer

Turn a codebase or bug report into evidence. When no bug is supplied, discover concrete candidates from the code and its contracts, then try to prove the strongest candidates with focused tests. Never present a suspicion as a confirmed bug.

Honor existing authority, then apply missing gates

Invocation alone to hunt for unknown bugs is inspection-only. A direct request to fix or implement a reported bug, or to find and fix bugs in a named repository, authorizes the normal reversible reproduction tests and causal production edits inside that stated task. A direct request to reproduce a reported bug or create its regression test likewise authorizes the normal reversible reproduction files and commands, but not a production repair. Record the matching task scope and proceed without stopping for duplicate confirmation, even when the exact responsible file is learned during diagnosis. Do not ask the user to approve the same scope twice.

If the user asked only to inspect, audit, find, or isolate, do not infer permission to create reproduction files or change production code. A direct reproduction or regression-test request authorizes only the normal reversible reproduction work described above; it does not authorize a production repair. Before a gate that has not been satisfied, do not create or edit project files, install dependencies, run formatters or migrations, modify configuration, generate reports, create worktrees, or execute commands likely to mutate project state. Read source, configuration, documentation, existing tests, user-supplied logs, and Git history. Run an existing targeted test only when it is clearly safe and does not require project changes.

Gate 1 — test the candidate

When the current request has not explicitly authorized creating and running a reproducer, present and stop at:

## Bug candidates

| # | Candidate | Contract evidence | Trigger | Location | Confidence |
|---|---|---|---|---|---|
| 1 | ... | ... | ... | file:line | high/medium |

## Proposed bug test

- Candidate(s) to test:
- Why each could be a real bug:
- Exact files to create or edit:
- Minimal fixture/input:
- Test or harness command:
- Signal that will confirm each bug:
- Main risk or uncertainty:

No project files have been modified. Do you want me to create and run these tests?

Read the full file on GitHub · 241 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.

  1. yesterday Changed · +10 lines 11792325ceef
  2. 5d ago First seen · 231 lines · 147 tokens per session scan A 4741d5f6951e

Subscribe to this mod's changes

bug-reproducer is a skill published in the GitHub repository AnastasiyaW/codex-claude-code-config (149 stars, last pushed 2d ago), licensed MIT. It adds 147 tokens to every session and 3,280 once invoked, about $0.0007 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 2026-09-05.

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