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Identify Assumptions Existing

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.

testing
By phuryn
23k2.3kUpdated 6 days agoMIT

Skill Content

## 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:

1. **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

2. **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?

3. **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

- [Assumption Prioritization Canvas: How to Identify And Test The Right Assumptions](https://www.productcompass.pm/p/assumption-prioritization-canvas)
- [How to Manage Risks as a Product Manager](https://www.productcompass.pm/p/how-to-manage-risks-as-a-product-manager)
- [Continuous Product Discovery Masterclass (CPDM)](https://www.productcompass.pm/p/cpdm) (video course)

How to use

  1. Copy the skill content above
  2. Create a .claude/skills directory in your project
  3. Save as .claude/skills/pm-skills-identify-assumptions-existing.md
  4. Use /pm-skills-identify-assumptions-existing in Claude Code to invoke this skill

GitHub stars License: MIT PRs Welcome Tests Companion: pm-skills Companion: burnstop Companion: claude-usage

PM Skills Marketplace: The AI Operating System for Better Product Decisions

68 PM skills and 42 chained workflows across 9 plugins. Claude Code, Cowork, and more. From discovery to strategy, execution, launch, growth, and shipping AI-built code.

PM Skills marketplace: skills, commands, and all 9 plugins at a glance

Designed for Claude Code and Cowork. Skills compatible with other AI assistants.

Start Here

New idea? → /discover
Need strategic clarity? → /strategy
Writing a PRD? → /write-prd
Planning a launch? → /plan-launch
Defining metrics? → /north-star

If this project helps you, ⭐ the repo.

Why PM Skills Marketplace?

Generic AI gives you text. PM Skills Marketplace gives you structure.

Each skill encodes a proven PM framework — discovery, assumption mapping, prioritization, strategy — and walks you through it step by step. You get the rigor of Teresa Torres, Marty Cagan, and Alberto Savoia built into your daily workflow, not sitting on a bookshelf.

The result: better product decisions, not just faster documents.

How It Works (Skills, Commands, Plugins)

Example prompts: a skill and two commands (/write-prd, /ship-check) in action

Skills are the building blocks of the marketplace. Each skill gives Claude domain knowledge, analytical frameworks, or a guided workflow for a specific PM task. Some skills also work as reusable foundations that multiple commands share.

Skills are loaded automatically when relevant to the conversation — no explicit invocation needed. If needed (e.g., prioritizing skills over general knowledge), you can force loading skills with /plugin-name:skill-name or /skill-name (Claude will add the prefix).

Commands are user-triggered workflows invoked with /command-name. They chain one or more skills into an end-to-end process. For example, /discover chains four skills together: brainstorm-ideas → identify-assumptions → prioritize-assumptions → brainstorm-experiments.

Plugins group related skills and commands into installable packages. Each plugin covers a PM domain — discovery, strategy, execution, and so on. Installing the marketplace gives you all 9 plugins at once.

Commands use skills. Some skills serve multiple commands. Some skills (like prioritization-frameworks or opportunity-solution-tree) are standalone references that Claude draws on whenever relevant — no command needed.

Commands are designed to flow into each other, matching the PM workflow. After any command completes, it suggests relevant next commands — just follow the prompts.

Installation

Claude Cowork (recommended for non-developers)

  1. Open Customize (bottom-left)
  2. Go to Browse pluginsPersonal+
  3. Select Add marketplace from GitHub
  4. Enter: phuryn/pm-skills

All 9 plugins install automatically. You get both commands (/discover, /strategy, etc.) and skills.

Installing PM Skills in Claude Cowork

Claude Code (CLI)

# Step 1: Add the marketplace
claude plugin marketplace add phuryn/pm-skills

# Step 2: Install individual plugins
claude plugin install pm-toolkit@pm-skills
claude plugin install pm-product-strategy@pm-skills
claude plugin install pm-product-discovery@pm-skills 
claude plugin install pm-market-research@pm-skills 
claude plugin install pm-data-analytics@pm-skills
claude plugin install pm-marketing-growth@pm-skills
claude plugin install pm-go-to-market@pm-skills
claude plugin install pm-execution@pm-skills
claude plugin install pm-ai-shipping@pm-skills

Codex CLI (OpenAI)

Codex reads the same plugin marketplace file as Claude Code, so you can install PM Skills natively — no conversion or file-copying needed:

# Step 1: Add the marketplace
codex plugin marketplace add phuryn/pm-skills

# Step 2: Install the plugins you want
codex plugin add pm-toolkit@pm-skills
codex plugin add pm-product-strategy@pm-skills
codex plugin add pm-product-discovery@pm-skills
codex plugin add pm-market-research@pm-skills
codex plugin add pm-data-analytics@pm-skills
codex plugin add pm-marketing-growth@pm-skills
codex plugin add pm-go-to-market@pm-skills
codex plugin add pm-execution@pm-skills
codex plugin add pm-ai-shipping@pm-skills

What you get: every skill (the PM frameworks), available to Codex and invocable by name. Install whole plugins rather than cherry-picking individual skills — a workflow usually relies on several skills that ship together.

What's different from Claude Code: the /slash commands (/discover, /write-prd, …) install but don't run as Codex slash commands — Codex plugins don't expose commands. To run a workflow, just describe the steps in plain language, for example:

Run product discovery on [your idea]: brainstorm options, map assumptions, prioritize the risky ones, then design experiments — pause between each step.

Optional — let Codex turn the workflows into skills. Because the command files ship inside each installed plugin, you can ask Codex to convert the ones you use most:

Read the command files in the pm-execution plugin and create equivalent Codex skills for the workflows I use most often.

This is a best-effort, model-driven conversion (some Claude-specific command syntax won't translate), but it's a quick way to get the guided workflows on Codex without leaving the CLI.

Other AI assistants (skills only)

The skills/*/SKILL.md files follow the universal skill format and work with any tool that reads it. Commands (/slash-commands) are Claude-specific.

ToolHow to useWhat works
Gemini CLICopy skill folders to .gemini/skills/Skills only
OpenCodeCopy skill folders to .opencode/skills/Skills only
CursorCopy skill folders to .cursor/skills/Skills only
KiroCopy skill folders to .kiro/skills/Skills only
# Example: copy all skills for OpenCode (project-level)
for plugin in pm-*/; do
  mkdir -p .opencode/skills/
  cp -r "$plugin/skills/"* .opencode/skills/ 2>/dev/null
done

# Example: copy all skills for Gemini CLI (global)
for plugin in pm-*/; do
  cp -r "$plugin/skills/"* ~/.gemini/skills/ 2>/dev/null
done

Available Plugins

<details> <summary><strong>1. pm-product-discovery</strong> — Ideation, experiments, assumption testing, OSTs, interviews (13 skills, 5 commands)</summary>

Skills (13):

  • brainstorm-ideas-existing — Multi-perspective ideation for existing products (PM, Designer, Engineer)
  • brainstorm-ideas-new — Ideation for new products in initial discovery
  • brainstorm-experiments-existing — Design experiments to test assumptions for existing products
  • brainstorm-experiments-new — Design lean startup pretotypes for new products (Alberto Savoia)
  • identify-assumptions-existing — Identify risky assumptions across Value, Usability, Viability, and Feasibility
  • identify-assumptions-new — Identify risky assumptions across 8 risk categories including Go-to-Market, Strategy, and Team
  • prioritize-assumptions — Prioritize assumptions using an Impact × Risk matrix with experiment suggestions
  • prioritize-features — Prioritize a feature backlog based on impact, effort, risk, and strategic alignment
  • analyze-feature-requests — Analyze and categorize customer feature requests by theme and strategic fit
  • opportunity-solution-tree — Build an Opportunity Solution Tree (Teresa Torres) — outcome → opportunities → solutions → experiments
  • interview-script — Create a structured customer interview script with JTBD probing questions
  • summarize-interview — Summarize an interview transcript into JTBD, satisfaction signals, and action items
  • metrics-dashboard — Design a product metrics dashboard with North Star, input metrics, and alert thresholds

Commands (5):

  • /discover — Full discovery cycle: ideation → assumption mapping → prioritization → experiment design
  • /brainstorm — Multi-perspective ideation (ideas|experiments × existing|new)
  • /triage-requests — Analyze and prioritize a batch of feature requests
  • /interview — Prepare an interview script or summarize a transcript (prep|summarize)
  • /setup-metrics — Design a product metrics dashboard

Examples:

Skills:

  • What are the riskiest assumptions for our AI writing assistant idea?
  • Help me build an Opportunity Solution Tree for improving user activation
  • Prioritize these 12 feature requests from our enterprise customers [attach CSV]

Commands:

  • /discover AI-powered meeting summarizer for remote teams
  • /brainstorm experiments existing — We need to reduce churn in our onboarding flow
  • /interview prep — We're interviewing enterprise buyers about their procurement workflow
</details> <details> <summary><strong>2. pm-product-strategy</strong> — Vision, business models, pricing, competitive landscape (12 skills, 5 commands)</summary>

Product strategy, vision, business models, pricing, and macro environment analysis. Covers the full strategic toolkit from vision crafting through competitive landscape scanning.

Skills (12):

  • product-strategy — Comprehensive 9-section Product Strategy Canvas (vision → defensibility)
  • startup-canvas — Startup Canvas combining Product Strategy (9 sections) + Business Model — an alternative to BMC and Lean Canvas for new products
  • product-vision — Craft an inspiring, achievable, and emotional product vision
  • value-proposition — 6-part JTBD value proposition (Who, Why, What before, How, What after, Alternatives)
  • lean-canvas — Lean Canvas business model for startups and new products
  • business-model — Business Model Canvas with all 9 building blocks
  • monetization-strategy — Brainstorm 3–5 monetization strategies with validation experiments
  • pricing-strategy — Pricing models, competitive analysis, willingness-to-pay, and price elasticity
  • swot-analysis — SWOT analysis with actionable recommendations
  • pestle-analysis — Macro environment: Political, Economic, Social, Technological, Legal, Environmental
  • porters-five-forces — Competitive forces analysis (rivalry, suppliers, buyers, substitutes, new entrants)
  • ansoff-matrix — Growth strategy mapping across markets and products

Commands (5):

  • /strategy — Create a complete 9-section Product Strategy Canvas
  • /business-model — Explore business models (lean|full|startup|value-prop|all)
  • /value-proposition — Design a value proposition using the 6-part JTBD template
  • /market-scan — Macro environment analysis combining SWOT + PESTLE + Porter's + Ansoff
  • /pricing — Design a pricing strategy with competitive analysis and experiments

Examples:

Skills:

  • Compare Lean Canvas vs Business Model Canvas vs Startup Canvas for my marketplace startup
  • Design a value proposition for our AI writing assistant targeting non-native English speakers
  • Run a Porter's Five Forces analysis for the project management SaaS market

Commands:

  • `/strategy B2B project manage

View source on GitHub