Sentinel Payment Boundary Tools

Read-only MCP preflights and a public quote-request draft tool for agent payment boundaries.

GitHub

Documentation

Sentinel Recovery Support

Public support and fixed-scope Ethereum evidence-service surface for Sentinel Recovery.

Live site: https://terminallylazy.github.io/sentinel-recovery-support/

Paid services: https://terminallylazy.github.io/sentinel-recovery-support/#services

Agent manifest: https://terminallylazy.github.io/sentinel-recovery-support/.well-known/sentinel-agent.json

The site exposes a human-readable funding page, $49/$99/$199 public-data services, and framework-neutral agent resources. A payer agent may send within its own delegated financial policy, and inbound receipts need no recipient-side human acceptance. Every outbound action from Sentinel's receiving wallet requires human authorization. Sentinel never takes custody, requests private keys or signature material, or promises recovery.

Public resources

  • / — funding purpose, exact Ethereum Mainnet tuple, terms, and verification links
  • /.well-known/sentinel-agent.json — agent capability and safety manifest
  • /support.json — exact wallet, network, assets, and funding terms
  • /support-intent.json — direction-specific payer and receiving-wallet policy
  • /services.json — fixed-price scope, deliverable, and turnaround catalog
  • /service-request.json — canonical agent input schema, email and public GitHub issue transports, and copyable quote-request template: https://terminallylazy.github.io/sentinel-recovery-support/service-request.json
  • /sample-agent-payment-boundary-review.json and .md — inspectable $49 self-review demonstration: JSON, Markdown
  • /sample-service-quote.json — complete but expired and explicitly nonpayable quote-shape demonstration
  • /sample-evidence-preview.json and .md — inspectable $99 format demonstration
  • /service-payment.json — canonical recipient, assets, quote fields, and verification rules
  • /privacy.json — minimal inputs, optional context, retention, and do-not-send rules
  • /agent-guide.md — mandatory agent authority boundaries
  • /impact.json — historical receipt and contribution-funded-work snapshot
  • /llms.txt — short discovery index
  • mcp/ — read-only stdio MCP server with deterministic agent-payment and x402 PaymentRequired preflights, a local public quote-request draft preparer, and the live service and quote-request resources; install from source or the checksummed v0.4.1 GitHub Release, not from the static Pages site

Local MCP preflight and resources

The source checkout is version 0.4.1 and exposes three deterministic read-only tools:

  • preflight_agent_payment_boundary — checks one or two inline public documents against 11 fixed payment-authority boundaries, without fetching requester URLs, executing supplied text, submitting a request, or moving funds
  • preflight_x402_v2_payment_required — checks one decoded inline x402 v2 PaymentRequired JSON document under a pinned, closed-world exact-EVM EIP-3009 Sentinel safety profile, without decoding headers, evaluating payer policy, verifying signatures or receipts, settling, connecting a wallet, or moving funds
  • prepare_agent_payment_boundary_quote_request — prepares a complete, unsubmitted public GitHub issue draft for the fixed-scope Agent Payment Boundary Review from one or two caller-supplied public HTTPS document URLs without credentials, query strings, fragments, or non-public hosts; it does not fetch or verify those URLs, make a network request, use credentials, submit the issue, authorize payment, or create service entitlement

It also exposes exactly two read-only resources:

  • sentinel://services/catalog
  • sentinel://services/quote-request-contract

Only resource reads fetch the two hard-coded canonical live JSON contracts. Both preflights run locally on inline content, and the request-draft preparer formats its inputs locally without fetching supplied URLs. All three tools make no network request and cannot submit a request, move funds, authorize payment, request credentials, connect a wallet, or create service entitlement. The requester decides whether to submit the public draft within its own communication authority; a Sentinel human controls issuance of the complete written quote, and any later payment remains controlled by the payer's own policy.

The checksummed v0.4.1 MCPB and its SHA-256 sidecar are published on the GitHub Release. The official MCP Registry lists version 0.4.1 as active and latest under io.github.TerminallyLazy/sentinel-recovery-services; verify the exact Registry record before relying on availability.

Install and verify it from the repository root:

npm ci --prefix mcp --ignore-scripts
npm test --prefix mcp
npm audit --prefix mcp --audit-level=high
npm run pack:check --prefix mcp

Configure an MCP client to launch the source checkout over stdio, replacing the path with the absolute path on that machine:

{
  "mcpServers": {
    "sentinel-recovery-services": {
      "command": "node",
      "args": ["/absolute/path/to/sentinel-recovery-support/mcp/server.mjs"]
    }
  }
}

Direct launch uses node mcp/server.mjs. Do not configure the GitHub Pages URL as an MCP endpoint: the static site does not implement Streamable HTTP. The npm package is not published yet, so no npx installation is advertised.

Human-approved service quotes

The quote path is deliberately local and human-triggered. The scripts/prepare-service-quote.mjs helper accepts public-only request JSON, but only runs after the operator supplies SENTINEL_HUMAN_APPROVAL=APPROVE. It creates a mode-0600 local artifact for human review. It does not issue or publish the quote, comment on an issue, request payment, or expand a payer agent's authority. There is intentionally no public GitHub Actions quote workflow because a live payable quote ID and payment reference should not be exposed as a public-repository artifact.

Prepare a live local quote and append its exact digest to a local approval registry (keep both paths outside the repository):

mkdir -p "$HOME/.local/state/sentinel-recovery"
chmod 700 "$HOME/.local/state/sentinel-recovery"
SENTINEL_HUMAN_APPROVAL=APPROVE \
SENTINEL_REQUEST_JSON="$(jq -c . /absolute/path/request.json)" \
SENTINEL_ASSET=USDC \
SENTINEL_VALIDITY_DAYS=7 \
SENTINEL_QUOTE_OUTPUT="$HOME/.local/state/sentinel-recovery/approved-quote.json" \
SENTINEL_QUOTE_REGISTRY="$HOME/.local/state/sentinel-recovery/approved-quotes.jsonl" \
npm run quote:prepare

The same deterministic formatter can run locally with operator-supplied UUID v4 identifiers and timestamps:

node scripts/create-service-quote.mjs \
  --request /absolute/path/request.json \
  --asset USDC \
  --quote-id 11111111-1111-4111-8111-111111111111 \
  --payment-reference 22222222-2222-4222-8222-222222222222 \
  --issued-at 2026-07-10T20:00:00.000Z \
  --expires-at 2026-07-17T20:00:00.000Z

Paid quotes support canonical USDC and canonical USDT only; their base-unit amounts are derived from the fixed integer USD catalog price. ETH remains a voluntary-support asset, not a quoted USD-denominated service asset. The raw formatter emits a nonpayable draft to standard output so a human can inspect it. Only the approval-gated local preparer emits a payable quote and records its digest in the operator's approved-quote registry.

After the requester returns a transaction hash, the read-only receipt checker can compare the confirmed canonical ERC-20 Transfer log to the exact approved quote tuple and reconcile it against an append-only local receipt ledger:

node scripts/verify-service-receipt.mjs \
  --quote /absolute/path/approved-quote.json \
  --quote-registry "$HOME/.local/state/sentinel-recovery/approved-quotes.jsonl" \
  --receipt-ledger "$HOME/.local/state/sentinel-recovery/service-receipts.jsonl" \
  --transaction-hash 0x... \
  --rpc-url "$SENTINEL_ETH_RPC_URL" \
  --confirmations 12

Use a trusted HTTPS Ethereum Mainnet JSON-RPC endpoint and keep credentialed RPC URLs out of issues, logs, and quote artifacts. The checker does not sign, broadcast, spend, or move funds; it requests no keys, signatures, or wallet connection. The local ledger makes repeated checks idempotent and routes a receipt reused across quotes to manual review instead of crediting it twice. The complete manual operator checklist is in docs/service-operations.md.

Local development

npm ci
npm run dev

To inspect the exact GitHub Pages artifact at its production base path:

npm run preview:pages

Validation

npm test
npm run lint
npm audit --audit-level=high
npm run export:pages