// technical prompt evaluation
Is your prompt actually ready?
Technical diagnosis, surgical fixes and version history — for those who take AI seriously.
3 free diagnoses per month · no credit card · cancel anytime
🔬
Diagnose before you ship
0-100 score with breakdown across clarity, specificity, structure and robustness — know what will break before it hits production
🔧
Fix without rewriting
production iterator: minimal surgical edits that fix the specific behavior without breaking what already works
📚
Roll back in seconds
versioned library with full history, per-version scores and diffs — compare and revert to any previous version (Pro)
✨
Automatically improved prompt
rewritten version with all fixes applied, preserving your original style and structure (Pro)
🧠
Advanced architecture analysis
context window, logical complexity, system/user prompt separation and agent decomposition suggestions (Pro)
🔒
Secure by design
server-side auth, Row Level Security on database, no card data stored
different from the rest
OpenAI and Anthropic tools are for experimentation.
PromptEval is for production.
Any playground gives you a "better prompt." PromptEval tells you exactly what will break in production, proposes minimal edits that don't affect the rest of your agent, and keeps full version history in case you need to roll back.
✓
Minimal edits that don't break agents
the iterator proposes only what's necessary — no full rewrite that risks unexpected behavior
✓
Version history with diffs
compare v1 vs v3, see exactly what changed and why the score went up or down
✓
Root cause diagnosis
not "your prompt is vague" — it's "critical instruction X is buried in the middle and being ignored"
Simple for experiments.
Serious for production.
no contracts, cancel anytime
FREE
$0
3 diagnoses/month
PRO
$19
/month · everything unlimited
TEAM
$49
/month · API + collaboration
Your agent deserves a prompt that doesn't break.
3 free diagnoses per month, no credit card required
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