thinking-partner — Claude Code plugin: mental models for decisions
Turns your agent into a sparring partner that questions assumptions, names the model it applies and asks one question at a time.
/plugin marketplace add anthropics/claude-plugins-community
/plugin install thinking-partner@claude-communityWhat thinking-partner does
This plugin runs a working session, not a lecture. It surfaces the beliefs you have been treating as facts, picks a framework that fits the situation, and keeps the problem open long enough for a real answer to show up. The catalog holds more than 150 models across 17 disciplines: first principles, inversion, pre-mortem, 5 Whys, game theory, Bayesian updating.
Orientation detection is the core mechanic. It diagnoses 6 thinking states (GT0–GT5) and matches an intervention to each one. From there a fixed 6-step route runs from diagnosis to synthesis, supported by 7 pairs of cognitive operations such as decouple/re-couple and hold/resolve. Anti-patterns are spelled out too, so the agent knows what to avoid.
It fires on prompts like “help me think through X”, “challenge my thinking”, “what am I missing”, “play devil's advocate”, or any named model: SWOT, inversion, pre-mortem. The skill follows the open Agent Skills standard, yet inside Claude you install it from the plugin marketplace rather than with npx skills add — two different routes, and mixing them up gets you nowhere.
What it helps with
- surface hidden assumptions you treat as facts
- pick the right mental model for a situation
- work through a choice between two options
- stress-test an idea before you commit
- catch reasoning that serves comfort over truth
Example prompts for the agent
- Help me think through moving the queue into its own service
- Challenge my plan to rewrite the auth layer
- Run a pre-mortem on this launch plan
How to install thinking-partner
Plugin marketplace
/plugin marketplace add anthropics/claude-plugins-community/plugin install thinking-partner@claude-communityStep by step, with commands for each platform: Claude Code plugins: marketplaces, installing, and building your own
Questions about thinking-partner
How do I install thinking-partner in Claude Code?
From the plugin marketplace: run /plugin marketplace add anthropics/claude-plugins-community first, then /plugin install thinking-partner@claude-community.
What does thinking-partner do?
It runs a structured session on your decision: diagnoses your thinking state, applies fitting mental models, and asks one question at a time.
How many mental models does it include?
More than 150, organised across 17 disciplines, from first principles and inversion to game theory and statistics.
Source text
SKILL.md · MIT
# Thinking Partner A deterministic thinking partner that challenges assumptions and applies 150+ mental models to sharpen decisions, solve problems, and think more clearly. Built on the open [Agent Skills](https://agentskills.io) standard. Works with Claude Code, Cursor, Windsurf, Cline, GitHub Copilot, and any AI agent that supports the standard. ## Install ```bash npx skills add mattnowdev/thinking-partner ``` ## What It Does Not a lecture — a sparring session. Turns your AI agent into a thinking partner that: - **Challenges assumptions** — Surfaces hidden beliefs you're treating as facts - **Applies mental models** — Selects and deploys the right frameworks for your situation (150+ models across 17 disciplines) - **Detects orientation capture** — Notices when your thinking serves comfort instead of truth - **Maintains productive tension** — Holds complexity open long enough to find real insight ## When It Triggers - "Help me think through X" - "Challenge my thinking" - "What am I missing?" - "Play devil's advocate" - "Stress test this idea" - "Help me decide between X and Y" - Any named mental model: SWOT, first principles, inversion, pre-mortem, 5 Whys, etc. ## What Makes It Different | Feature | This Skill | Others | |---|---|---| | **Orientation Detection** | Diagnoses 6 thinking states (GT0-GT5) with targeted interventions | Generic questioning | | **150+ Mental Models** | Full catalog organized by discipline with key questions | Handful of models | | **Cognitive Operations** | 7 complementary operation pairs (Decouple/Re-couple, Hold/Resolve, etc.) | None | | **Structured Workflow** | 6-step deterministic process from diagnosis to synthesis | Freeform | | **Anti-Patterns** | Explicit guidance on what NOT to do | None | ## Mental Models Included Organized across 17 disciplines: - **General Thinking**: First Principles, Inversion, Second-Order Thinking, Chesterton's Fence, Entropy, and more - **Decision-Making**: Pre-Mortem, Regret Minimization, SWOT, Asymmetric Risk, Preserving Optionality - **Problem-Solving**: 5 Whys, Fishbone, MECE Decomposition, Bright Spots Analysis, Local vs Global Optima - **Systems & Complexity**: Feedback Loops, Stocks & Flows, Tipping Points, Antifragility, Path Dependence - **Economics & Strategy**: Incentives, Network Effects, Tragedy of the Commons, Lindy Effect, Power Laws - **Statistics & Probability**: Bayesian Updating, Correlation vs Causation, Selection Bias, Gambler's Fallacy - **Psychology & Biases**: Confirmation Bias, Planning Fallacy, Halo Effect, Curse of Knowledge, Peak-End Rule - **Physics & Engineering**: Inertia, Activation Energy, Resonance, Half-Life, Margin of Safety - **Biology & Evolution**: Natural Selection, Red Queen Effect, Coevolution, Niche Construction - **Communication & Persuasion**: Steel Manning, Reciprocity, Narrative/Storytelling, Pyramid Principle - **Creativity & Innovation**: SCAMPER, Design Thinking, Oblique Strategies, Minimum Viable Experiment - **Learning & Development**: Feynman Technique, Spaced Repetition, Zone of Proximal Development - **Time & Resource Management**: Eisenhower Matrix, Pareto Principle, Maker's vs Manager's Schedule - **Game Theory**: Prisoner's Dilemma, Schelling Point, Tit for Tat, Signaling, Moral Hazard - **Negotiation**: BATNA, ZOPA, Logrolling - **Resilience & Antifragility**: Barbell Strategy, Skin in the Game, Via Negativa, Hormesis - **Ethics & Responsibility**: Veil of Ignorance See the full catalog in [`skills/thinking-partner/references/model-catalog.md`](skills/thinking-partner/references/model-catalog.md). ## Alternative Install <details> <summary>Manual install per agent</summary> **Claude Code** ```bash git clone https://github.com/mattnowdev/thinking-partner.git cp -r thinking-partner/skills/thinking-partner ~/.claude/skills/thinking-partner ``` **Cursor** ```bash git clone https://github.com/mattnowdev/thinking-partner.git cp -r thinking-partner/skills/thinking-partner .cursor/skills/thinking-partner ``` **Windsurf** ```bash git clone https://github.com/mattnowdev/thinking-partner.git cp -r thinking-partner/skills/thinking-partner .windsurf/skills/thinking-partner ``` **Other Agents** Copy the `skills/thinking-partner/` directory (including `references/`) into your agent's skills directory. </details> ## License MIT
© mattnowdev · MIT · mattnowdev/thinking-partner
