Reasoning semiformally
Skill oaustegard/claude-skills/plugins/code-intelligence/skills/reasoning-semiformally
Apply semi-formal certificate reasoning to code analysis — patch verification, fault localization, patch equivalence. Use when reviewing patches, hunting bugs across scopes, comparing fixes, or when code reasoning requires tracing execution across files/modules. Triggers on code review, bug localization, patch comparison, name shadowing, scope analysis, regression checking.From its SKILL.md
npx -y skills add oaustegard/claude-skills --skill reasoning-semiformallyAssembled from the repository path, not quoted from the project. Check it against their README if it does not work.
SKILL.md
1.5 KB, 243 tokens by cl100k_base, as published. Nobody here has run it
Semi-Formal Code Reasoning
Structured certificate templates that force mandatory checkpoints before conclusions.
Skip Conditions
Do NOT apply semi-formal reasoning when:
- The change is trivial: docs, formatting, version bumps, config changes
- The bug is locally obvious: typo, off-by-one in the same function, missing comma
- No execution paths cross scope boundaries
- The task is not code analysis (text editing, data extraction, summarization)
If any skip condition is met, proceed with standard reasoning.
Model-Specific Instructions
If you are Haiku-class (Haiku 4.5 or similar):
Read haiku.md in this skill directory. It contains full procedural templates with worked examples.
If you are Sonnet-class or above (Sonnet 4.6, Opus):
Read sonnet.md in this skill directory. It contains compact verification checkpoints.
Composing Tasks
For complex tasks, apply templates sequentially:
- Fault localization to find the bug
- Patch verification to validate a proposed fix
- Patch equivalence to compare alternative fixes
Each output feeds the next as premises.
What ships with it: 3 files
12.2 KB alongside SKILL.md