Assumption Mapper Skill

Surface and prioritize the untested assumptions embedded in any product plan before development begins.

Required Inputs

Ask the user for these if not provided:

• Product brief, PRD, or concept description (even rough notes work)
• Stage (concept / discovery / pre-build / post-launch — affects which assumptions matter most)

Process

1. Read the provided brief, PRD, or concept description
2. Extract assumptions across four categories:

• Desirability (do users want this?)
• Feasibility (can we build it?)
• Viability (will it sustain the business?)
• Usability (can users actually use it?)

1. Score each assumption:

• Confidence (1-5): How sure are we this is true?
• Impact (1-5): How badly does the plan fail if this assumption is wrong?
• Priority = Impact − Confidence (higher = test first)

1. Validate completeness — Ensure at least one assumption per category. If a category is empty, re-read the brief looking specifically for that type.
2. Output a ranked list with recommended validation methods

Output Structure

Assumption Map: [Feature/Product Name]

#### Critical Assumptions (Impact 4+ and Confidence 2 or below) [Flagged items with detailed validation recommendations]

#### Top 3 Assumptions to Validate First [Detailed recommendations including specific research method, estimated effort, and what the result would change]

Example (Partial)

Input: "We're building a self-serve onboarding flow to reduce time-to-value for SMB customers."

Anti-Patterns

• [ ] Do not only surface desirability assumptions — feasibility and viability assumptions are equally likely to kill a product and are often overlooked
• [ ] Do not assign high confidence to an assumption just because it hasn't been challenged yet — absence of evidence is not evidence
• [ ] Do not recommend "user interviews" as the validation method for every assumption — some assumptions require quantitative data, competitive analysis, or technical spikes
• [ ] Do not list assumptions that cannot be tested — every assumption in the map must have a plausible validation method, or it should be flagged as unknowable and treated as a risk

Quality Checks

• [ ] At least one assumption per category (Desirability, Feasibility, Viability, Usability)
• [ ] All Impact 4+ / Confidence 2− assumptions flagged as CRITICAL
• [ ] Each validation method is specific (not just "do research" — name the method and sample size)
• [ ] Priority scores are consistent (Impact − Confidence, higher = more urgent)