Vigil — an outside witness for AI agents

Agent leases, signed receipts, watchdogs, and optional paid source-verification evidence.

CommunityOnlineNo sign-inGlobalFreeRead-only

What it can do

    What data it sees

    Do you need an account

    No: the server works without sign-in

    Agent leases, signed receipts, watchdogs, and optional paid source-verification evidence.

    How to connect

    How to connect Vigil — an outside witness for AI agents to Claude

    The server address to paste into Claude settings:

    https://vigilnotary.com/mcp

    1. Open Claude (claude.ai or the desktop app).
    2. Go to Settings → Connectors.
    3. Click Add custom connector.
    4. Paste the server address copied below into Remote MCP server URL and click Add.
    5. In a chat, click + → Connectors and switch the new connector on.

    Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

    Authorization

    After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

    How to connect Vigil — an outside witness for AI agents to ChatGPT

    The server address to paste into ChatGPT settings:

    https://vigilnotary.com/mcp

    1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
    2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
    3. Open Settings → Connectors and click Create.
    4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
    5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
    6. In a new chat open + → Apps/Connectors and enable the connector.

    OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

    Authorization

    On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

    How to connect Vigil — an outside witness for AI agents to Cursor

    The server address to paste into Cursor settings:

    https://vigilnotary.com/mcp

    Fastest: click Open in Cursor below and confirm the prompt.

    Manually:

    1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
    2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
    3. Save the file. The server appears in the MCP list; authorize it there if asked.

    Authorization

    If the service needs sign-in, an authorize button appears next to the server in the MCP list.

    Server tool list (26)

    Raw names from tools/list. Only developers need these.

    vigil_infoService description, the Ed25519 signing pubkey to verify receipts against, current chain head, and free-tier limits. No key required.
    vigil_registerCreate a key. Returns a bearer key shown ONCE — store it; it is your only identity. No email, no account. Starts on the free tier. Creates a persistent identity. The returned key grants full account control; provision it in a trusted client, not a model transcript.
    vigil_pricingThe plans and per-tier limits (free, dev, pro). No key required.
    vigil_usageYour current tier, its limits, and how much you've used today. Requires your key.
    vigil_notarizeNotarize work: POST the sha256 (64 hex chars) of anything and get back an Ed25519-signed, timestamped, hash-chained, serial-numbered receipt. Chain position orders submitted records; the timestamp is a signed assertion of Vigil's clock. Free tier: 10/day. Irreversibly publishes the digest, label and account handle in the public chain; no deletion tool exists. It proves signed-data integrity, not that an action happened or a claim is true.
    vigil_get_receiptFetch a receipt by serial number. Public — anyone can read any receipt.
    vigil_verify_receiptVerify a receipt's hash and Ed25519 signature against a mandatory, independently pinned Ed25519 public key. The key must not come from the receipt being checked. Returns valid=false for tampering, forgery, a wrong signer, or malformed input. Read-only and local to Vigil.
    vigil_chainRead a range of receipts to audit chain continuity. Max 1000 per call.
    vigil_set_watchdogArm a dead-man switch. Register an interval and an https webhook; then call vigil_heartbeat before each interval elapses. Miss one and Vigil attempts a signed 'absence' payload to your webhook, retrying failed delivery. Free tier: 1 watchdog. Overwrites an existing watchdog and resets its timer and delivery state. A missed heartbeat sends the supplied message to an external HTTPS recipient; failed delivery is capped at five attempts per armed interval.
    vigil_heartbeat'Still alive.' Reset a watchdog's timer. Call this at least once per interval. Resets the deadline and delivery state, potentially suppressing an overdue alert or rearming delivery.
    vigil_watchdog_statusRead a watchdog's state: interval, last beat, whether it is overdue, fired, or exhausted.
    vigil_delete_watchdogRemove a watchdog. Destructive: deletes its configuration and stops future alerts. No undo or restoration of the previous timer is provided.
    vigil_grant_leaseGrant a short-lived, Ed25519-signed LEASE authorizing an agent to perform an action until it expires. A customer-run gateway verifies the lease offline (fail-closed) before letting the action through. This is the guard on a money/data-moving action. Free tier: 1 active lease (guarded agent). Security-sensitive: grants authority. Keep this account key outside the controlled agent. A signed lim string is enforced only by the customer's gateway.
    vigil_renew_leaseExtend a lease with a fresh signed token and new expiry. Renewing is how a healthy agent keeps acting; stop renewing (or revoke) and it lapses. Security-sensitive: extends authority and refreshes the offline recheck window. Keep renewal credentials outside the controlled agent.
    vigil_revoke_leaseRevoke a lease. A compliant v2 gateway refuses the old offline token at recheck_by_ms (at most 30 seconds after issue/renewal), or earlier if it polls revocation. Revocation is not instantaneous. Irreversible for this lease ID; it cannot be renewed again. Already admitted actions are not undone.
    vigil_lease_statusPublic status of a lease (active / expired / revoked). What a gateway polls for revocation. No key required.
    vigil_verify_leaseOffline, FAIL-CLOSED check of a lease token against a mandatory, independently pinned Ed25519 public key. Returns allow=true only for a valid signature before expiry and recheck_by_ms. It does not authenticate the calling agent, enforce action/amount policy, or query live revocation; a customer gateway must do those checks before every provider action. Checks signature, expiry and the signed recheck deadline only. It does not check live revocation, agent identity, action, amount or gateway policy; those checks are mandatory at the gateway.
    vigil_leasesList your leases and their states.
    vigil_anchorsPublic timestamp submissions to OpenTimestamps calendars. A submission is pending, not an independently verified Bitcoin confirmation. No key required.
    vigil_anchorPRO: anchor the current chain head to OpenTimestamps on demand (the chain is auto-anchored every few hours regardless). Sends the public chain-head digest to external OpenTimestamps calendars; submission is not verified Bitcoin confirmation.
    vigil_journal_putStore an opaque blob under a slug (overwrites). Encrypt client-side: the server stores exactly the bytes supplied and cannot enforce client encryption. Send bytes as base64. Free tier: 4 slots, 64KB each. Destructive when the slug exists: previous bytes are replaced with no version history or undo.
    vigil_journal_getFetch a journal blob by slug. Returns base64 (decrypt client-side).
    vigil_journal_listList your journal slots (slug, size, last-updated).
    vigil_journal_deleteDelete a journal slot. Destructive: removes stored bytes with no undo through the API.
    vigil_revoke_keyRevoke your own key. It stops authenticating immediately. Irreversible. Irreversible: also revokes the account's leases and deletes its watchdogs. Private journal access is lost; public receipts remain. It does not cancel a Stripe subscription.
    vigil_verify_sourcePaid source-local verification with exact evidence and signed receipt. Does not establish absolute truth. Read price and payment requirements before authorizing; settlement spends USDC irreversibly and there is no automatic refund. Identical tool arguments alone are NOT idempotent: retry with the identical arguments, same vigil/idempotency-key metadata and original payment proof.