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Understand the core mental model behind QWED in one page.

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

1

1) Receive natural language input

Example: β€œIs the sum of triangle angles 180 degrees?”
2

2) Translate to a structured form

LLM maps intent into DSL, symbolic expression, or typed schema.
3

3) Verify with deterministic engine

QWED uses engines like SymPy, Z3, AST analyzers, and SQL parsers.
4

4) Return a proof-backed result

Final status is returned with evidence, not just confidence.

One concrete example

from qwed_sdk import QWEDClient

client = QWEDClient(api_key="qwed_your_key")

result = client.verify_logic("(AND (GT x 5) (LT y 10))")
print(result.status)  # SAT
print(result.model)   # {"x": 6, "y": 9}

Determinism vs probability

CharacteristicLLM-only flowQWED flow
Output consistencyVaries by run/promptStable for same input
Correctness basisStatistical likelihoodFormal or rule-based verification
Failure visibilityOften implicitExplicit statuses and proofs
Production safetyRisky without guardsBuilt for verification gates

Verification statuses

StatusMeaning
VERIFIEDClaim is valid and accepted
FAILEDClaim is invalid
CORRECTEDClaim was wrong and corrected
INCONCLUSIVEExpression evaluated deterministically, but the translation from natural language was not formally verified. Check the trust_boundary field for details
BLOCKEDSecurity or policy violation detected
ERROREngine could not complete verification

Where each engine fits

EngineTypical 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
SchemaStructured output integrity

Attestations and auditability

QWED can generate signed attestations so downstream systems can verify that a check occurred:
result = client.verify("2+2=4", include_attestation=True)
print(result.attestation)  # signed token
Use this for compliance, audit logs, and third-party verification.

Next steps

  1. Quick Start
  2. Architecture Overview
  3. Verification Engines
  4. Attestation Spec