The trust boundary
QWED is built on a simple idea:LLMs are useful translators, not final authorities.The important boundary is between translation and verification:
- Before verification: output is untrusted.
- After deterministic verification: output is accepted, corrected, or blocked.
How verification actually works
3) Verify with deterministic engine
QWED uses engines like SymPy, Z3, AST analyzers, and SQL parsers.
One concrete example
Determinism vs probability
| Characteristic | LLM-only flow | QWED flow |
|---|---|---|
| Output consistency | Varies by run/prompt | Stable for same input |
| Correctness basis | Statistical likelihood | Formal or rule-based verification |
| Failure visibility | Often implicit | Explicit statuses and proofs |
| Production safety | Risky without guards | Built for verification gates |
Verification statuses
| Status | Meaning |
|---|---|
VERIFIED | Claim is valid and accepted |
FAILED | Claim is invalid |
CORRECTED | Claim was wrong and corrected |
INCONCLUSIVE | Expression evaluated deterministically, but the translation from natural language was not formally verified. Check the trust_boundary field for details |
BLOCKED | Security or policy violation detected |
ERROR | Engine could not complete verification |
Where each engine fits
| Engine | Typical use |
|---|---|
| Math (SymPy) | Equations, identities, numeric claims |
| Logic (Z3) | Constraints, SAT/UNSAT, model generation |
| Code (AST/symbolic) | Vulnerability and unsafe pattern detection |
| SQL (parser/rules) | Injection prevention and query validation |
| Schema | Structured output integrity |