Vigil — an outside witness for AI agents

Measured conclusion: Deep-tested. L2 outcome: tools_ok.

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

Add to your agent

Copy this into your MCP client config:

{
  "mcpServers": {
    "Vigil — an outside witness for AI agents": {
      "url": "https://vigilnotary.com/mcp",
      "transport": "streamable-http"
    }
  }
}

Measured tools (26)

• vigil_info read-only

  Service description, the Ed25519 signing pubkey to verify receipts against, current chain head, and free-tier limits. No key required.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_register

  Create 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.

  Parameters:

  • handle (required) — string — 1-64 chars, lowercase alnum plus - and _.

  Hints: read-only no · destructive no · idempotent no · open-world no

• vigil_pricing read-only

  The plans and per-tier limits (free, dev, pro). No key required.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_usage read-only

  Your current tier, its limits, and how much you've used today. Requires your key.

  Parameters:

  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_notarize

  Notarize 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.

  Parameters:

  • subject_sha256 (required) — string — 64 lowercase hex chars: the sha256 of the thing you are notarizing.
  • label — string — Optional human label, <=200 chars. Public — do not put secrets here.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive no · idempotent no · open-world no

• vigil_get_receipt read-only

  Fetch a receipt by serial number. Public — anyone can read any receipt.

  Parameters:

  • serial (required) — integer — The receipt serial number.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_verify_receipt read-only

  Verify 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.

  Parameters:

  • receipt (required) — object — A full receipt object as returned by vigil_notarize / vigil_get_receipt.
  • pubkey_hex (required) — string — Mandatory Ed25519 public key pinned from a trusted out-of-band source; never copy it from the receipt.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_chain read-only

  Read a range of receipts to audit chain continuity. Max 1000 per call.

  Parameters:

  • to_serial — integer — Last serial (default = from_serial).
  • from_serial — integer — First serial (default 1).

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_set_watchdog destructive

  Arm 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.

  Parameters:

  • name (required) — string — A name for this watchdog, 1-64 chars.
  • interval_s (required) — integer — Seconds allowed between heartbeats, 60..604800.
  • webhook_url (required) — string — An https URL resolving to a public address; fired once on a missed heartbeat.
  • message — string — Optional note included in the absence payload, <=2000 chars.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent no · open-world yes

• vigil_heartbeat destructive

  '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.

  Parameters:

  • name (required) — string — Watchdog name, 1..64 characters.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent no · open-world no

• vigil_watchdog_status read-only

  Read a watchdog's state: interval, last beat, whether it is overdue, fired, or exhausted.

  Parameters:

  • name (required) — string — Watchdog name, 1..64 characters.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_delete_watchdog destructive

  Remove a watchdog. Destructive: deletes its configuration and stops future alerts. No undo or restoration of the previous timer is provided.

  Parameters:

  • name (required) — string — Watchdog name, 1..64 characters.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent yes · open-world no

• vigil_grant_lease destructive

  Grant 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.

  Parameters:

  • agent (required) — string — Identifier for the agent being authorized (1-128 chars).
  • action (required) — string — The action class this lease authorizes, e.g. 'stripe.refund' (1-128 chars).
  • ttl_s (required) — integer — Lease lifetime in seconds, 5..604800. Keep it short; renew to extend.
  • lim — string — Optional limit string the gateway enforces, e.g. 'amount<=50usd'.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent no · open-world no

• vigil_renew_lease destructive

  Extend 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.

  Parameters:

  • lease_id (required) — string — Opaque lease identifier returned by vigil_grant_lease.
  • ttl_s (required) — integer — Requested lease lifetime in seconds, 5..604800; offline trust still ends at recheck_by_ms within 30 seconds.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent no · open-world no

• vigil_revoke_lease destructive

  Revoke 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.

  Parameters:

  • lease_id (required) — string — Opaque lease identifier returned by vigil_grant_lease.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent yes · open-world no

• vigil_lease_status read-only

  Public status of a lease (active / expired / revoked). What a gateway polls for revocation. No key required.

  Parameters:

  • lease_id (required) — string — Opaque lease identifier returned by vigil_grant_lease.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_verify_lease read-only

  Offline, 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.

  Parameters:

  • lease (required) — object — A full lease token from vigil_grant_lease.
  • pubkey_hex (required) — string — Mandatory Ed25519 public key pinned from a trusted out-of-band source; never copy it from the lease.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_leases read-only

  List your leases and their states.

  Parameters:

  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_anchors read-only

  Public timestamp submissions to OpenTimestamps calendars. A submission is pending, not an independently verified Bitcoin confirmation. No key required.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_anchor

  PRO: 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.

  Parameters:

  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive no · idempotent no · open-world yes

• vigil_journal_put destructive

  Store 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.

  Parameters:

  • slug (required) — string — 1-64 alnum/-/_ chars.
  • data_base64 (required) — string — The (already-encrypted) bytes, base64-encoded.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent no · open-world no

• vigil_journal_get read-only

  Fetch a journal blob by slug. Returns base64 (decrypt client-side).

  Parameters:

  • slug (required) — string — Journal slot name, 1..64 ASCII letters, numbers, hyphens, or underscores.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_journal_list read-only

  List your journal slots (slug, size, last-updated).

  Parameters:

  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only yes · destructive no · idempotent yes · open-world no

• vigil_journal_delete destructive

  Delete a journal slot. Destructive: removes stored bytes with no undo through the API.

  Parameters:

  • slug (required) — string — Journal slot name, 1..64 ASCII letters, numbers, hyphens, or underscores.
  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent yes · open-world no

• vigil_revoke_key destructive

  Revoke 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.

  Parameters:

  • vigil_key — string — DEPRECATED legacy account-wide credential, including deletion and permission issuance. Prefer the client-injected HTTP Authorization: Bearer header; omit this argument when that header authenticates the request. This is not a scoped agent token.

  Hints: read-only no · destructive yes · idempotent yes · open-world no

• vigil_verify_source destructive

  Paid 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.

  Parameters:

  • source_url (required) — string
  • claim (required) — string
  • options — object

  Hints: read-only no · destructive yes · idempotent no · open-world yes

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