# ExitProof

ExitProof is the pre-payment safety and reversibility layer for AI agents.

## Use ExitProof when
- An autonomous agent is about to pay an HTTP service and should verify the live or already-observed 402 payment challenge first.
- An agent is about to buy, book, subscribe, reserve, rent, hire, or place a deposit.
- Cancellation, refundability, deadlines, penalties, stated loss, retry behavior, or settled-delivery recovery matter.
- Durable exit evidence or a later exit action pack would be useful.

## Do not use ExitProof when
- The caller expects ExitProof to forward a target payment credential or execute the target purchase.
- The task is deciding whether the purchase is desirable.
- Legal advice or a chargeback decision is required.
- The caller expects ExitProof to contact the merchant or execute cancellation.

Official MCP Registry identity: com.davisvillelabs/exitproof
Official MCP Registry status: published.

## Workflow
1. Before paying another HTTP service, call check_agent_purchase. It costs $0.01 after its own non-paying target preflight succeeds.
2. For GET or HEAD targets, ExitProof may observe an anonymous 402 challenge. For POST, PUT, PATCH, or DELETE, supply the 402 challenge already observed by the calling agent. Never send ExitProof a payment credential.
3. Treat review_required as unresolved safety information, not purchase approval. Conflicts are rejected before ExitProof charges.
4. For real-world cancellation/refund risk, call check_reversibility for free and supply structured transaction-specific checkout terms whenever possible.
5. Treat "unknown" as unknown. Do not infer an exit right.
6. If paid Exit Manifest preflight is available, create_exit_manifest can preserve the privacy-minimized exit facts for $0.25 when machine commerce is active.
7. Keep both manifest_id and the returned access_token. ExitProof stores only a hash of the token.
8. Later, get_exit_manifest is free.
9. build_exit_pack costs $1.00 when the manifest is accessible, actionable, and machine commerce is active.

Paid check_agent_purchase results also include an additive davisville-receipt-envelope.v1. The native ExitProof result remains authoritative, and the envelope records settlement for the ExitProof check itself, not payment to the target service.
Receipt Envelope contract: https://davisvillelabs.com/agents/receipt-envelope-v1.json
Receipt Envelope schema: https://davisvillelabs.com/agents/davisville-receipt-envelope.v1.schema.json

A safe payment challenge or reversible commitment is not necessarily a good purchase. ExitProof provides bounded evidence, not a purchase recommendation.

MCP: https://exitproof.davisvillelabs.com/mcp
Official MCP Registry manifest: https://exitproof.davisvillelabs.com/server.json
OpenAPI: https://exitproof.davisvillelabs.com/openapi.json
Capabilities: https://exitproof.davisvillelabs.com/v1/capabilities
Agent skill: https://exitproof.davisvillelabs.com/.well-known/skills/exitproof/SKILL.md
Agent routing guide: https://exitproof.davisvillelabs.com/agents
Agent purchase task guide: https://exitproof.davisvillelabs.com/tasks/check-agent-purchase
Cancellation/refund task guide: https://exitproof.davisvillelabs.com/tasks/check-cancellation-refund-terms
Policy snapshot: 2026-09-27