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Foundation Sprint Magic Lenses: Brainshelf Book Catalog (Day 2 Afternoon)

Scenario

The Brainshelf team is in Day 2 afternoon. Approach Options is signed; 5 candidates advance. Jamie invokes tool-foundation-sprint-magic-lenses to evaluate each through 4 classic plus 1 custom lens and name a top bet + backup.

Approach labels: A=Yellow Camera, B=Blue Library, C=Green Voice, D=Red Bookstore, E=Purple Triage.

Customer Lens

Question: Which approach do target customers immediately understand and want?

ApproachCustomer perceptionPosition
Yellow Camera”I get it. Point and capture.”HV-HF
Blue Library”Pretty. But I don’t have books to put in it yet.”MV-HF (chicken-and-egg)
Green Voice”Cool, but I talk to my phone in public?”MV-LF
Red Bookstore”Wait, you do that?” (delight)VHV-LF
Purple Triage”Like Pocket for books. Sure.”MV-HF

Top per Customer Lens: Yellow (broad), Red (deep delight).

Pragmatic Lens

ApproachBuild costRisk
Yellow CameraMedium (OCR + cover-recognition; Apple Vision API available)Acceptable
Blue LibraryLow (CRUD + UI polish)Low
Green VoiceHigh (voice quality + book entity resolution)High
Red BookstoreHigh (geofence + offline book DB)Very high
Purple TriageLow-medium (share extension + queue UI)Low

Top per Pragmatic Lens: Blue, Yellow.

Growth Lens

ApproachWhy people would tell a friend
Yellow Camera”I just snap books.” Decent.
Blue Library”My library looks nice.” Low signal.
Green VoiceHigh novelty IF voice quality holds.
Red Bookstore”It tells me at the bookstore if I’ve already read it.” Highest novelty.
Purple Triage”Pocket for books.” Low novelty.

Top per Growth Lens: Red, Green, Yellow.

Money Lens

ApproachMonetization story
Yellow CameraFree tier with limit; paid sync + cross-device. Familiar.
Blue LibrarySame as Yellow; aesthetic premium possible.
Green VoiceSame as Yellow; voice is free differentiator.
Red BookstoreBookstore mode could be a premium feature.
Purple TriageTriage capacity could tier (Pocket precedent).

Top per Money Lens: Similar across all; slight edge to Blue and Red.

Custom Lens 1: Defensibility Against Goodreads / Amazon

ApproachDefensible?
Yellow CameraNo. Goodreads has cover scanning today.
Blue LibraryPartially. Brainshelf principles (private, no feed) are strategically distinct.
Green VoiceYes. Goodreads unlikely to commit to voice.
Red BookstoreYes. Amazon-owned Goodreads is awkward for geofencing bookstores.
Purple TriagePartially. The triage pattern is well-known.

Top per Defensibility Lens: Red, Green.

Pattern Review

Consistent winners: Yellow (positive on 4 of 5 lenses), Red (positive on 4 of 5 lenses).

Consistent losers (eliminated):

  • Blue: chicken-and-egg empty library at launch.
  • Green: feasibility risk too high for the differentiation it provides.
  • Purple: doesn’t carry the “did I read this?” recall pain hard enough.

Contradictions:

  • Red is high on Customer + Growth + Money + Defensibility but failing Pragmatic. Hardest to ship; highest leverage if shipped.
  • Yellow is positive across all five but never #1 on any single lens. Strong consistent middle.

Biggest trade-off: Boring-and-shippable (Yellow) versus risky-and-distinctive (Red).

Top Bet (Decider Supervote)

Top bet: Approach A (Yellow Camera-First Capture).

Rationale: The riskiest assumption for Brainshelf is not “is this concept appealing” (Red would tell us that). The riskiest assumption is “will people switch from doing nothing to using a tracking app at all if friction drops below 3 seconds?” Yellow tests that hypothesis most directly. If Yellow succeeds, Red becomes a Phase 2 differentiator. If Yellow fails, Red doesn’t save the product.

Backup Plan

Backup: Approach D (Red Bookstore Mode).

If the Design Sprint test of Yellow shows weak adoption (“customers nod but don’t actually capture”), Brainshelf pivots to lead with bookstore-mode delight. Recall-at-context becomes the wedge, capture follows. This is a strategically distinct direction (context-driven recall) not an iteration of Yellow.

Decision Rationale

The team converged on Yellow over Red because the test value of Yellow is higher. Validating the core capture-speed differentiator early de-risks every downstream investment. Red is more delightful but tests a narrower part of the product. Better to know if the foundation works first.

Decider Checkpoint

Decider sign-off required before Founding Hypothesis writing begins.

  • Jamie names Yellow (Camera-First Capture) as the top bet.
  • Jamie names Red (Bookstore Mode) as the backup, strategically distinct from Yellow.
  • Jamie commits to NOT building Yellow as a Camera with Red features grafted on.
  • Jamie agrees to test the Yellow top bet via the planned Design Sprint week of May 26.

Signed: Jamie (founder, PM), 2026-05-14 15:40 PT