Borrowing it
Nothing to install: this file belongs to markmhendrickson/foundation. 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/markmhendrickson/foundation/main/.cursor/skills/fix-feature-bug/SKILL.mdgit clone --depth 1 https://github.com/markmhendrickson/foundationWrote 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/markmhendrickson/foundation/fix-feature-bug)<a href="https://agentmods.dev/skills/markmhendrickson/foundation/fix-feature-bug"><img src="https://agentmods.dev/badge/skills/markmhendrickson/foundation/fix-feature-bug/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/markmhendrickson/foundation/fix-feature-bug"><img src="https://agentmods.dev/badge/skills/markmhendrickson/foundation/fix-feature-bug.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 | $0.00017 | $0.00750 |
| Opus 5.5 | $0.00007 | $0.00300 |
| Sonnet 5.5 | $0.00003 | $0.00150 |
| Haiku 4.5 | $0.00002 | $0.00075 |
Grade A, and why
fix-feature-bug 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
92% identical to fix-feature-bug — 9 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 — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Fix Feature Bug
Fix a bug in a feature or module.
Configuration is read from foundation-config.yaml.
This workflow can also be triggered automatically via .cursor/rules/bug_fix_detection.md (or foundation/agent_instructions/cursor_rules/bug_fix_detection.md) when you mention bug/error-related patterns in natural language (e.g., "bug", "error", "fix", "broken"). Both paths execute the same workflow.
Workflow
-
Load configuration:
- Read
foundation-config.yamlfor bug fix settings - Check if error classification is configured
- Determine feature/module directory structure
- Read
-
Identify feature/module from error, path, or context.
-
Load relevant documents:
- Repository navigation guide (if configured)
- Feature/module spec and manifest (if available)
- Error classification documentation (if configured)
- Relevant subsystem/module documentation (if configured)
-
Classify bug (if error classification configured):
- Use configured error classification system
- Determine correction approach based on class
-
Apply correction rules:
- If Class 1 (Implementation bug): Patch code only
- If Class 2 (Spec bug): Update spec/manifest first, then align code/tests
- If Class 3 (Architectural bug): Update subsystem/architecture docs first, then rebuild
- If no classification: Fix bug and update relevant documentation
-
Always add a regression test.
-
Run tests:
- Run configured test commands
- Verify fix doesn't break existing functionality
-
Output:
- Error class (if classification configured)
- Reason for classification
- Corrected files
- Tests added/updated
Error Classification (Configurable)
If development.bug_fix.error_classification.enabled: true in foundation-config:
- Class 1: Implementation bug - spec is correct, code doesn't match spec
- Action: Patch code only
- Class 2: Spec bug - spec is incomplete or wrong, code matches spec but spec is wrong
- Action: Update spec/manifest first, then align code/tests
- Class 3: Architectural bug - subsystem/architecture docs are wrong or incomplete
- Action: Update architecture docs first, then rebuild
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 · 101 lines · 17 tokens per session scan A 76aea90259f6
fix-feature-bug is a skill published in the GitHub repository markmhendrickson/foundation (2 stars, last pushed 2mo ago), licensed MIT. It adds 17 tokens to every session and 750 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 92% identical to fix-feature-bug, differing in 9 lines, and is treated as a copy.
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