Decide between two options
Weigh two options against your constraints and find the cheapest test that would change the answer.
by Appndo
Tested on GPT-6.1 Sol, Claude Opus 5.5, Gemini 3.8 Flash · Verified Oct 28, 2026
The prompt
Help me decide between {{option A}} and {{option B}}.
Goal: {{goal}}
Constraints: {{constraints}}
1. Name the 2–4 criteria that actually separate these options for my goal, and rate each high, medium or low in importance given my constraints. Skip criteria that would not change the answer.
2. For each criterion, say which option is stronger and why. Write "unknown" where it depends on information I have not given.
3. Say how reversible each choice is and what switching later would cost.
4. Name what would flip the decision: the facts or results that would make the other option the better one.
5. Recommend A, B, or neither (with a better path), and give the cheapest test most likely to change that recommendation.
Do not give numeric scores or totals. Do not invent performance data, prices or benchmarks; if a number matters, say where to check it. Keep it brief.How to use it
Fill in the variables, for example: - option A: Postgres on a managed host - option B: Cloudflare D1 - goal: choose the database for a new SaaS run by one developer - constraints: under $50 a month, 10 hours a week, launch in 8 weeks The more specific your constraints, the more useful the comparison. Run the suggested test before committing.
Example
Inputs
- option A
- Postgres on a managed host (for example Neon or Supabase)
- option B
- Cloudflare D1
- goal
- Choose the primary database for a new B2B scheduling and invoicing tool built and run by one developer.
- constraints
- Under $50/month for the first year, about 10 hours a week, frontend and API already on Cloudflare Workers, knows Postgres but never used D1, customers want reports over 12 months of invoices, launch in 8 weeks.
Output
Recommend A: managed Postgres. Your Postgres experience and eight-week launch make delivery time the strongest deciding factor. Workers hosting alone isn’t enough reason to learn D1 for this launch.
| Criterion | Importance | Stronger option and why |
|---|---|---|
| Shipping and maintaining within your time budget | High | Postgres: you already know it. D1 adds learning and compatibility checks; Postgres adds connection setup from Workers. |
| Twelve-month invoice reporting | High | Postgres: more SQL flexibility and a familiar path for complex reporting. Whether D1’s SQLite-based SQL is sufficient is unknown without representative reports and data volumes. Twelve months alone doesn’t establish scale. |
| Staying below your monthly budget | High | Unknown: depends on data size, query frequency, report scans, and the host’s billing model. Check current plans, usage limits, overages, and backup costs for each candidate. |
| Integration with your existing Workers API | Medium | D1: native bindings simplify database access and avoid managing an external Postgres connection path. Whether that saves meaningful ongoing work is unknown. |
Reversibility
- Postgres → another Postgres host: relatively easy; move schema and data, update connections, and verify provider-specific features.
- Postgres ↔ D1: materially harder in either direction. Budget for schema/type changes, SQL rewrites, transaction and concurrency checks, data migration, and a tested cutover. Switching becomes costlier once reports and billing workflows depend on database-specific behavior. Keep database access localized and migrations versioned.
What would flip the decision to D1: your real reports work cleanly in SQLite, representative report and concurrent-write tests pass, D1’s current limits and recovery options meet your needs, and its verified cost or operational savings outweigh the learning time. A Postgres configuration that cannot meet your budget would also reopen the decision.
Cheapest useful test: time-box a D1 spike with synthetic invoices at your expected first-year volume. Run your hardest twelve-month report while creating invoices and attempting conflicting bookings. Check correctness, query effort, usage, and applicable limits. D1 becomes compelling if that test is straightforward and its cost estimate beats a viable Postgres setup; otherwise, launch on managed Postgres.
One real run with the example above. Results vary between runs and models.