Compare one prototype prompt across three builders
Run one narrow, identical prototype brief through v0, Bolt, and Lovable, then manually score the untouched outputs before choosing a direction.
Why
Why it earns its place
A controlled comparison reveals prompt adherence and broken interactions more honestly than product claims. It calibrates expectations, not a permanent tool ranking.
How
Run it
Freeze one brief
Define one user, one task, two screens, and three required interactions. Use invented names and values; exclude accounts, integrations, uploads, and real data.
Run it unchanged
Paste the same brief once into v0, Bolt, and Lovable. Record the initial output and generation time without revisions, visual references, or repair prompts.
Test the same path
Manually attempt every required interaction in each build. Log missing screens, dead controls, navigation errors, invented scope, and any behaviour you could not verify.
Score, then decide
Compare prompt adherence, functionality, responsive behaviour, and visual usefulness. Choose a direction for this task only, or reject all three and rewrite the brief.
Ready to paste
Prompt
Create a disposable responsive-web prototype for evaluation, not production.
User: [fictional user role]
Task: [one task]
Screen 1: [overview and required content]
Screen 2: [detail or form and required content]
Required interactions:
1. [interaction]
2. [interaction]
3. [interaction]
Use only synthetic data: [invented examples]. Do not request personal information, connect external services, call a network API, create authentication, or claim data is saved. Keep the scope to these two screens. If something is unspecified, label it TBD rather than inventing another feature.
At the end, list the screens and interactions implemented, assumptions made, and behaviours that need manual testing.The AIdea layer
The designer’s call
- Human core
- A person defines the benchmark, tests every path, and chooses; generated polish cannot stand in for working behaviour.
- The trade
- Parallel outputs expose differences but consume time and may favour defaults. Use one frozen brief and a shared scorecard.
- Skip AI when
- Skip the comparison when one approved tool is mandated or the prototype requires real integrations or sensitive data.
Check before use
Watch out
Use only invented content and no accounts, integrations, or personal data. Initial builds can contain dead controls and routing errors; test the same path in each output and do not infer current tool quality from one trial.
Source of truth
Evidence
One practitioner illustrated a single same-prompt comparison with untouched outputs; v0 omitted scope, Bolt's tested path worked, and Lovable returned 404 errors.
Xinran Ma · I ran the same prompt through three popular AI prototyping tools