Theorist

Maintain a per-repo THEORY.MD as a continuously updated narrative of the operating theory behind the current work. Activates EVERY session and stays active throughout the session. Requires frequent in-session rewrites as new learnings land (major result, verification outcome, or strategy pivot). Not a log, not a plan, not a todo list — a cohesive document describing the higher-level thinking, systematic strategy, and motivation behind the work as it evolves. Updated end-to-end (rewritten, not appended) as understanding deepens.

192 stars 10 forksTesting & QA

Install

skills CLI (Claude Code, Cursor, Codex and more)

npx skills add blader/theorist --skill theorist

Manual install

git clone --depth 1 https://github.com/blader/theorist.git /tmp/theorist
mkdir -p ~/.claude/skills
cp -r /tmp/theorist/. ~/.claude/skills/theorist

Personal skills live in ~/.claude/skills. Use .claude/skills in a project folder to share a skill with your team.

From the SKILL.md

# Theorist

You maintain a per-repo narrative document at `THEORY.MD` that captures
the operating theory of the work being done. This is not a plan, not a log, not
a task list. It is a living essay that describes *why* the work exists, *what*
the systematic strategy is, and *how* the current approach connects to the
larger picture.

**This skill is always active during every session. No trigger required.**
**Once active in a session, it stays active for the full session.**

## What THEORY.MD Is

A cohesive narrative document — typically 1-3 pages — that a thoughtful
collaborator could read to understand:

- **The problem thesis**: What problem is being solved and why it matters.
  Not "fix bug X" but "the export pipeline assumes Y, which breaks under Z."
- **The operating theory**: The current mental model of how the system works
  and where the leverage points are. What has been tried, what was learned,
  and what that implies about the shape of the solution.
- **The systematic strategy**: Not task-by-task steps, but the higher-order
  approach. Why this sequence of work? What principle connects the changes?
- **Key discoveries and pivots**: Moments where understanding shifted. What
  was the old theory, what broke it, and what replaced it.
- **Open questions and uncertainties**: What is still unknown. Where the
  current theory might be wrong. What would change the approach.

## What THEORY.MD Is Not

Read the full skill on GitHub

Details

Skill name: theorist
Repository: blader/theorist
License: MIT
Repo updated: 28 February 2026

FAQ

What does the Theorist skill do?

How do I install the Theorist skill?

skills CLI (Claude Code, Cursor, Codex and more): npx skills add blader/theorist --skill theorist. Skills go in ~/.claude/skills (personal) or .claude/skills (project), and Claude loads them automatically when a task matches the description.

Is Theorist popular?

It lives in blader/theorist, which has 192 GitHub stars and 10 forks.

Related skills

Clarify Intent and Establish Shared Understanding

206

Inference1/clarify-intent-and-establish-shared-understanding

Whether you're thinking or getting things done, be clear, specific, and methodical. Grounded in first principles, rigorously examine and refine a user's task, decision, plan, goal, strategy, proposal, or idea through structured, progressively deeper questioning, in order to bridge the gap between the User and the Agent. Use when the user explicitly requests grilling, challenge, pressure-testing, cross-examination, red-team review, pre-mortem analysis, or a decision audit. The goal is to uncover unclear objectives, hidden assumptions, contradictions, weak evidence, missing information, overlook

Testing & QA

Supercov

159

supercorp-ai/supercov

Measures test coverage and code quality in a repository with the supercov CLI, and turns what it finds into small, focused tests or fixes. Use when the user asks to add or improve tests, find untested code or raise coverage, or find what to refactor. Works with JavaScript, TypeScript, Python, Ruby, Rust, Go, Java and Kotlin projects.

Testing & QAIn 1 list

Venice Responses

160

veniceai/skills

Use Venice's Alpha POST /responses endpoint - an OpenAI-compatible, stateless Responses API with typed output blocks (reasoning, message, function_call, web_search_call). Covers request shape, input items, tools (function, web_search, x_search), reasoning controls, incomplete responses, streaming events, differences from /chat/completions, the supported venice_parameters subset, and E2EE behavior.

Testing & QAIn 1 list27

Integrate Whatsapp

195

gokapso/agent-skills

Connect WhatsApp to your product with Kapso: onboard customers with setup links, detect connections, receive events via webhooks, and send messages/templates/media. Also manage WhatsApp Flows (create/update/publish, data endpoints, encryption). Use when integrating WhatsApp end-to-end.

Testing & QAIn 1 list27

Persona

takechanman1228/claude-persona

Build a persona panel, explore customer motivations through open-ended questions, and pressure-test product concepts before spending on fieldwork. Generates diverse AI persona panels, runs agent-separated interviews (qualitative ask or structured concept test), analyzes results with theme synthesis, cross-tabs, and charts, and delivers executive research reports. Use when the user wants to ask a panel about motivations or barriers, which concept to launch, who to target first, which message resonates, whether a value proposition works, or needs a reusable persona panel.

Testing & QAIn 2 lists

Pict Test Designer

102

omkamal/pypict-claude-skill

Design comprehensive test cases using PICT (Pairwise Independent Combinatorial Testing) for any piece of requirements or code. Analyzes inputs, generates PICT models with parameters, values, and constraints for valid scenarios using pairwise testing. Outputs the PICT model, markdown table of test cases, and expected results.

Testing & QAIn 3 lists11

Browse the most popular Claude skills, all testing & qa skills, or write your own with the skills generator.