Decision Frameworks

Iron Law

NO GENERIC ADVICE — every framework must be applied to the specific situation the user describes; "consider your assumptions" is not an application; naming the actual assumptions is

Decision Frameworks

Four single-framework deep-dives for decisions, problems, and commitments. Each mode applies one reasoning framework interactively — asking follow-up questions, pushing for specificity, and refusing vague answers.

Use this skill when you want to go deep on one framework. Use mental-model-applier when you want three frameworks applied in parallel for a broader perspective shift.

When to Use This Skill

• You are stuck on a specific problem and want to reason through it systematically
• A decision keeps feeling hard despite having information — you need a different lens
• You want to challenge your own assumptions before committing
• You are about to make an irreversible choice and want to stress-test it
• You need to make tradeoffs explicit rather than implicit

The Four Modes

| Mode | Framework | Best For | |------|-----------|----------| | First Principles | Break to fundamental truths, rebuild | Overcoming convention, designing from scratch, "why do we do it this way?" | | Inversion | Guarantee failure, then flip | Risk surfacing, strategy validation, pre-commitment checks | | Regret Minimization | Decide from age 80 | Long-horizon personal or career decisions, emotional clarity | | Opportunity Cost | Make tradeoffs visible | Commitments, resource allocation, "should I do this?" decisions |

Mode Selection

Ask the user which framework to apply if they have not specified one. Present the four options with a one-line description. Use AskUserQuestion when interactive mode permits.

If the user's problem maps clearly to one mode, state which you are using and why before beginning.

Core Workflow

1. Read the problem — Understand what is being decided or solved. If the description is vague, ask one clarifying question before proceeding.
2. Select mode — Match to the problem type using the table above, or ask.
3. Load reference — Read the corresponding reference file for the full method and output template.
4. Apply interactively — Do not produce a monologue. Ask follow-up questions. Push for specificity. Refuse vague answers.
5. Produce structured output — Use the output template from the reference file.
6. Offer a second pass — After completing one mode, offer to run a complementary framework.

Reference Guide

| Mode | Reference File | Load When | |------|---------------|-----------| | First Principles | references/first-principles.md | User wants to break assumptions and rebuild | | Inversion | references/inversion.md | User wants to work backwards from failure | | Regret Minimization | references/regret-minimization.md | User faces a long-horizon personal or career decision | | Opportunity Cost | references/opportunity-cost.md | User is evaluating a commitment or resource allocation |

Constraints

MUST DO

• Apply the framework specifically to the user's situation — name their actual assumptions, their actual tradeoffs, their actual failure modes
• Push back on vague answers: "poor execution" is not a failure mode; "the API migration slips 3 weeks because the external team has no SLA" is
• Ask follow-up questions rather than filling gaps with invention
• State which framework you are applying and why before starting
• End with a concrete output the user can act on — not just analysis

MUST NOT DO

• Apply multiple frameworks simultaneously — this skill is for single-framework depth; use mental-model-applier for multi-model breadth
• Produce generic advice that would apply to any situation
• Accept "it depends" as a final answer — push for the specific version that applies here
• Skip the interactive element and produce a monologue

Complementary Framework Pairings

After completing one mode, suggest a natural follow-on:

| Completed Mode | Natural Follow-On | Why | |----------------|-------------------|-----| | First Principles | Inversion | First Principles finds the right foundation; Inversion stress-tests it | | Inversion | Second-Order Thinker | Inversion finds failure modes; Second-Order maps their downstream consequences | | Regret Minimization | Opportunity Cost | Emotional clarity on direction + explicit tradeoffs of the chosen path | | Opportunity Cost | First Principles | Tradeoffs made visible + assumptions challenged on why those options exist |

Related

> For adversarially stress-testing any decision or plan: use the-fool skill. > For applying three frameworks in parallel for perspective shift: use mental-model-applier skill. > For mapping downstream consequences of a decision: use second-order-thinker skill.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: kumaran-is
• Source: kumaran-is/claude-code-onboarding
• License: MIT

Install and usage instructions live in the source repository linked above.