How do I install the Reasoning Semiformally skill?

Run npx skillmds@latest add oaustegard/reasoning-semiformally in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Reasoning Semiformally safe to use?

This skill has not completed SkillMD's automated safety review yet. Capability flags: docs only. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Reasoning Semiformally?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Reasoning Semiformally free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Reasoning Semiformally?

oaustegard (@oaustegard) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Reasoning Semiformally by oaustegard

Name: Reasoning Semiformally
Rating: 4.5 (4 reviews)
Author: oaustegard

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.

oaustegard 377dd22 5 files · 14.3 KB Updated Sep 10, 2026

File contents

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 5, 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.

Frequently asked questions