Tools & Resources

Assumption Mapper

When to use: At the very start of validation, after completing your Lean Canvas in Playbook 01. Re-run whenever you pivot or significantly change your business model.

What it does: Takes your business model as input and generates a comprehensive list of assumptions classified by D.V.F.+S risk category (Desirability, Viability, Feasibility, Strategic). Each assumption is ranked by impact and uncertainty, producing a clear testing priority sequence.

Key output: A prioritized assumption map with your "Leap of Faith" assumptions highlighted. This directly drives which experiments you run first.

Framework reference: Chapter 3 (Epistemological Foundations) covers the D.V.F.+S framework and Assumption Mapping Matrix in detail.

Interview Script Generator

When to use: Before every round of customer interviews. Update the script as you learn -- each round should build on insights from the previous one.

What it does: Generates a Mom Test-compliant interview script tailored to your customer segment and the specific assumptions you're testing. Includes warm-up questions, problem exploration questions, JTBD-style questions, and commitment-seeking closing questions. Automatically flags any questions that violate Mom Test principles.

Key output: A ready-to-use interview guide with 15-20 questions, organized by interview phase, with probing follow-up suggestions for each section.

Framework reference: Chapter 4 (Qualitative Discovery) covers the Mom Test, JTBD framework, and the discovery interview script in depth.

Insight Survey Builder

When to use: After your qualitative interviews have revealed patterns that need quantitative verification. Not a substitute for interviews -- a complement to them.

What it does: Helps you design bias-free surveys with proper screening questions, randomized answer orders, and appropriate Likert scales. Includes sample size calculators and flags common survey design mistakes (double-barreled questions, leading language, hypothetical framing).

Key output: A polished survey ready for distribution, with statistical guidance on how many responses you need for meaningful results and how to interpret the data.

Framework reference: Chapter 5 (Quantitative Verification) covers survey design principles and statistical reality checks.

Market Signal Tester

When to use: When you need behavioral evidence that goes beyond what interviews and surveys can provide. Use this to design landing page tests, fake door experiments, concierge MVPs, and other revealed-preference experiments.

What it does: Helps you design experiments using the standard template: "We believe [audience] will [action] for [reason]. We'll know we're right if [metric] reaches [threshold] within [timeframe]." Includes CTA Strength Ladder recommendations and threshold benchmarks by industry.

Key output: A complete experiment plan with hypothesis, method, success criteria, kill criteria, and gray zone protocols -- all defined before you start.

Framework reference: Chapter 6 (Behavioral Economics) covers smoke tests, fake door experiments, and the CTA Strength Ladder.

Problem-Solution Fit Analyzer

When to use: After gathering both qualitative and quantitative evidence. This tool synthesizes multiple data sources to assess whether your proposed solution genuinely addresses the problem you've uncovered.

What it does: Takes your interview insights, survey results, and experiment data as inputs. Evaluates the alignment between the problem (as customers describe it) and your solution (as you've designed it). Identifies gaps, misalignments, and areas where your solution exceeds or falls short of customer expectations.

Key output: A fit assessment with specific recommendations for improving alignment. Highlights which aspects of your solution customers would find most valuable and which they'd find unnecessary.

Framework reference: Chapters 4-7 collectively build the evidence base that this tool synthesizes.

Pivot Evaluator

When to use: At decision points -- when you've completed a round of experiments and need to decide whether to persevere, pivot, or kill the current direction.

What it does: Implements the Pivot Compass framework from Chapter 7. Takes all your evidence as input and maps it to the four Pivot Compass quadrants (Product-Market Fit, False Positive, Solution Mismatch, Dead End). If a pivot is recommended, suggests the specific type of pivot most supported by the evidence.

Key output: A structured pivot/persevere/kill recommendation with supporting evidence, confidence level, and suggested next actions for each option.

Framework reference: Chapter 7 (Synthesis & Decision) covers the Pivot Compass, pivot types, kill criteria, and decision biases.

Essential Books

• The Mom Test by Rob Fitzpatrick -- The definitive guide to customer interviews. Short, practical, and immediately applicable. If you read one book on validation, make it this one.
• Testing Business Ideas by David Bland and Alex Osterwalder -- A comprehensive library of 44 experiment types organized by evidence strength. Excellent reference for experiment design.
• Running Lean by Ash Maurya -- Translates Lean Startup principles into a step-by-step process. Strong on the Lean Canvas and iterative validation cycles.
• The Lean Startup by Eric Ries -- The foundational text on validated learning, the Build-Measure-Learn loop, and the pivot. Required reading for understanding the philosophy behind the practice.
• Competing Against Luck by Clayton Christensen -- The definitive work on Jobs to Be Done theory. Essential for understanding what customers are really "hiring" your product to do.

Free Online Resources

• Strategyzer's Testing Library -- Free experiment templates and hypothesis canvases from the creators of the Business Model Canvas.
• LeanPivot Validated Learning Guide -- Our comprehensive guide to the Build-Measure-Learn loop with practical examples.
• Steve Blank's Blog -- Regular posts on customer development methodology from the father of the Lean Startup movement.
• First Round Review -- Case studies and tactical advice from founders who've navigated the validation stage successfully.
• Lenny's Newsletter -- Practical product management advice including sections on validation, product-market fit metrics, and customer research techniques.