Validity + Synthesa

Spell-check for decision logic.

It reads your rules and shows you every case they silently fail to handle. Exhaustively. With a receipt anyone can re-check.

And once your decision space is proven solid, a cheaper model does the work just as well — prove once, then slash your token budget. See the benchmarks

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refund_policy.ruleslive
check_completeness(policy)gap found20 cases · exhaustive2 undecided

The 30-second aha

Paste a policy. Watch it find the case you never decided — the one where the bug ships.

check_completeness(refund_policy)

  complete: false   ·   3 situations your rules never decide:
     within window · item opened        -> undetermined
     after window  · enterprise tier      -> undetermined  (rule A and rule B collide)
     already refunded · payment disputed -> undetermined

  → the case you didn't decide is exactly where someone guesses in production.

No sampling, no test suite — it decides over the whole input space and names the exact gaps and contradictions. Then it seals a signed receipt an auditor re-verifies with the vendor absent.

Find yourself

New · Security & supply chain

Prove which CVEs can actually hurt you

The VEX Analyst.

Kill the 90% of scanner findings that aren't reachable in your deployment — with a proof, not a heuristic — and emit an OpenVEX receipt your customers re-check offline. Ready for the EU Cyber Resilience Act.

Start here →
Product manager

Find the holes in your PRD before the sprint

The requirement engineering will silently guess — and the two that contradict.

Developer / SDET

Catch decision bugs with the exact input that breaks them

A failing case you paste straight into a regression test.

Security engineer

No access decision that silently fails open

The request your policy never decided, and the rules that both grant and deny.

Policy / compliance

Prove a regulated rule set is complete — hand the auditor proof

No fail-open hole, no contradiction, re-checkable air-gapped.

AI / agent builder

Gate the agent's action with a proof, recorded

Every allow/deny a receipt; the undecided case routes to a human.

DMN / business-rules owner

Audit your decision table for gaps, conflicts, dead rules

The combination your table forgot — proven, not eyeballed.

Underwriting / eligibility

Prove the rating rules decide every applicant

The profile where a sicker patient is denied and a healthier one qualifies.

Markets / contracts desk

Find the case the contract forgot

The situation a covenant doesn't determine — where the dispute lives.

QA / test engineer

Find the cases your tests will never hit

One row per untested situation — your missing-test matrix, proven.

Program manager

Prove the program integrates before integration week

The seam where team B assumes a value team A never guarantees.

Auditor / regulator

Verify the vendor's claim yourself, air-gapped

No engine, no network — a public key and the receipt.

…and anything bounded

A decision that must handle every case

COLREGs collision-avoidance, patch source-contracts, pricing tiers, refund rules.

Don't see yours? If it's a decision that must handle every case — and today a human eyeballs it and hopes — that's us. Writing a persona takes a page; the guide shows you how.
Why a receipt

They have dashboards. You have proof.

Every result seals a signed, offline-verifiable receipt. A skeptic — an auditor, a regulator, a customer — re-checks it with only a public key. No engine, no network, no trusting you. That's the difference between "we say it's complete" and "here, prove it yourself."

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