identify-assumptions-existing
phuryn/pm-skills
Surface risky assumptions across Value, Usability, Viability, and Feasibility for existing product features.
What is identify-assumptions-existing?
Stress-tests a feature idea for an existing product by analyzing it from Product Manager, Designer, and Engineer perspectives. Identifies assumptions that could cause failure and suggests ways to validate them. Use when evaluating feature concepts, assessing risks, or preparing assumption maps.
- Analyzes feature ideas from three perspectives: Product Manager (business viability), Designer (usability), and Engineer (technical feasibility)
- Identifies risky assumptions across four risk areas: Value, Usability, Viability, and Feasibility
- Documents confidence levels (High/Medium/Low) for each assumption
- Suggests specific tests or validation methods for each assumption
- Provides constructive analysis aimed at strengthening ideas rather than dismissing them
How to install identify-assumptions-existing
npx skills add https://github.com/phuryn/pm-skills --skill identify-assumptions-existingHow to use identify-assumptions-existing
- 1.Describe your product, target market segment, and the feature idea you want to stress-test
- 2.Provide any supporting materials (designs, PRDs, research) if available
- 3.The skill will analyze the feature from Product Manager, Designer, and Engineer perspectives
- 4.Review the identified assumptions organized by risk area (Value, Usability, Viability, Feasibility)
- 5.Use the suggested tests to validate or invalidate each assumption before proceeding
Use cases
- Stress-testing a new feature concept before committing engineering resources
- Conducting risk assessment during product planning or roadmap review
- Preparing assumption maps for stakeholder alignment and discovery planning
- Evaluating whether a feature solves a real customer problem or creates unnecessary complexity
- Identifying integration risks and technical challenges before design handoff
- Product Managers evaluating feature viability
- Design and engineering teams reviewing feature concepts
- Product teams preparing for assumption validation and testing
- Anyone conducting pre-launch risk assessment
identify-assumptions-existing FAQ
This skill uses structured devil's advocate thinking across three distinct perspectives and explicitly identifies testable assumptions with confidence levels, rather than general feedback.
Use it early—ideally during concept or PRD stage—so you can validate assumptions before significant design or engineering work begins.
That's valuable. The goal is to surface what could go wrong so you can either test it or consciously accept the risk. Disagreement often reveals unstated assumptions.
High confidence assumptions are risky because you're confident they're true but they might not be. Low confidence assumptions need validation before proceeding. Prioritize testing Medium and High confidence items.
Full instructions (SKILL.md)
Source of truth, from phuryn/pm-skills.
name: identify-assumptions-existing description: "Identify risky assumptions for a feature idea in an existing product across Value, Usability, Viability, and Feasibility. Uses multi-perspective devil's advocate thinking. Use when stress-testing a feature idea, doing risk assessment, or preparing for assumption mapping."
Identify Assumptions (Existing Product)
Devil's advocate analysis to surface risky assumptions across four risk areas.
Context
You are stress-testing a feature idea for $ARGUMENTS.
If the user provides files (designs, PRDs, research), read them first.
Instructions
The user will describe their product, objective, market segment, and feature idea. Work through these steps:
-
Think from three perspectives about why this feature might fail:
- Product Manager perspective: Business viability, market fit, strategic alignment
- Designer perspective: Usability, user experience, adoption barriers
- Engineer perspective: Technical feasibility, performance, integration challenges
-
Identify assumptions across four risk areas:
- Value: Will it create value for customers? Does it solve a real problem?
- Usability: Will users figure out how to use it? Is the learning curve acceptable?
- Viability: Can marketing, sales, finance, and legal support it?
- Feasibility: Can it be built with existing technology? Are there integration risks?
-
For each assumption, note:
- What specifically could go wrong
- How confident you are (High/Medium/Low)
- Suggested way to test it
Think step by step. Be thorough but constructive — the goal is to strengthen the idea, not kill it.
Further Reading
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