Independent verification for the numbers your AI says.

NumProof checks numeric and financial claims deterministically — VERIFY / REFUTE with cell-level provenance — and returns a signed receipt anyone can re-check offline. An agent can recompute a number itself; it can’t issue an attestation a second party trusts. Not an LLM judge.

Read the docs →
VERIFY / REFUTEexact rational arithmetic, not a model judge
signed receiptre-check offline, zero trust
cell provenancespreadsheet & covenant audits

Agent claim gate

No API key required for this demo.
Ready.

Spreadsheet audit demo

Revenue1000
Gross Profit600
Gross Margin (=B2/B1)60%
Formula Sum (=SUM(B1:B2))1600

Runs through public MCP audit_rows, so the result is free and signed when signing is configured.

Ready.

Report diff demo

Revenue draft1000
Revenue final1100
Gross Profit600
New Metric9

Runs through public MCP diff_rows and returns a signed changed/added/removed bundle.

Ready.

API surface

EndpointUse
/verifyone claim, x402 or API key
/verify/batchCI and agent batches
/verify/auditsigned paid audit bundle
/verify/diffsigned report version diff
/verify/covenantssigned covenant rule-pack checks
/sample/finance-covenantspublic signed finance sample
/rule-packseditable covenant starter templates
/audit/verifypublic signature verification

Read the API docs, compare plans, open the finance workflow, run paid samples, verify a signed bundle, inspect rule packs, request a finance pilot, get an API key, or top up credits for paid audit, diff, covenant, batch checks, and proof artifacts.

MCP tools

ToolUse
verify_claimclaim verdict and counterexample
audit_rowssigned spreadsheet audit
diff_rowssigned report version diff
covenant_rulesbounded rule-pack checks

Hosted MCP descriptor points clients to /mcp.