mpazaryna/feynman-inquiry

Dev Inquiry

Feynman-style technical inquiry for developers. Understand before you decide. Validate before you build.

"The first principle is that you must not fool yourself—and you are the easiest person to fool." — Richard Feynman

Inquiry Modes

This skill supports four modes that often chain together:

| Mode | When to Use | Trigger Phrases | |------|-------------|-----------------| | Investigate | Understand something unfamiliar | "explore", "understand", "how does X work" | | Spike | Validate approach before building | "spike", "validate", "prove this works" | | Compare | Evaluate options for your context | "compare", "vs", "which is better" | | Decide | Make a concrete choice | "should we", "decide", "recommend" |

How to Use This Skill

1. Identify the mode from the user's request
2. Load the appropriate reference:
   • Investigation → Read references/investigation.md
   • Spike validation → Read references/spike.md
   • Comparison → Read references/scoring.md
   • Decision → Read references/scoring.md (uses comparison + decision framework)
3. Follow the workflow in that reference
4. Chain if needed — investigation often leads to spike, spike informs comparison

Mode Details

Investigate Mode

For understanding unfamiliar technology from first principles.

Process: Admit ignorance → Simplest experiment → Poke edges → Build mental model → Explain simply

Output: Mental model you can teach to someone else

Spike Mode

For validating technical feasibility before full implementation.

Process: Define scope (4-8 hours) → Write tests first → Implement minimal → Test with real data → Document pattern

Output: Proven pattern ready to replicate, or pivot decision

Compare Mode

For evaluating multiple options against your specific context.

Process: Define context → Choose criteria → Weight by importance → Score with evidence → Sanity check

Output: Weighted comparison matrix with evidence

Decide Mode

For making a concrete choice with documented reasoning.

Process: Ensure understanding (investigate if needed) → Compare options → State recommendation → Document tradeoffs → Assess reversibility

Output: Clear recommendation with rationale and risks

The Natural Flow

"Let's explore @Observable"
        ↓ Investigation
"Can I actually build nested observation?"
        ↓ Spike (validates understanding)
"@Observable vs @StateObject for my app"
        ↓ Comparison
"Should we adopt the new Observation framework?"
        ↓ Decision

Each mode builds on the previous. Don't decide before you understand. Don't compare before you investigate.

Quick Reference

| Request | Mode | Reference | |---------|------|-----------| | "Let's explore Swift macros" | Investigate | references/investigation.md | | "I want to understand async/await" | Investigate | references/investigation.md | | "Spike SwiftData before we commit" | Spike | references/spike.md | | "Validate this architecture works" | Spike | references/spike.md | | "Compare REST vs GraphQL" | Compare | references/scoring.md | | "SwiftData vs CoreData?" | Compare | references/scoring.md | | "Should we use Combine?" | Decide | references/scoring.md | | "Recommend an approach" | Decide | references/scoring.md |

Examples

For concrete examples across all modes, see references/examples.md.