Excalibur MCP

Official67 toolsLive

by lonniev · TypeScript

FastMCP server for posting formatted content to X (Twitter) — Tollbooth-monetized, DPYC-native

🛠️ Key Features

MCP server implementation for posting formatted content to X (Twitter)
Tollbooth-monetized access model
DPYC-native integration

🚀 Use Cases

Programmatically publish prepared content to X
Automate monetized content distribution workflows
Integrate with DPYC-native data pipelines for posting

⚡ Developer Benefits

Clear, minimal MCP server interface for posting to X
Monetization-aware access control via Tollbooth
Native DPYC compatibility for streamlined deployments

⚠️ Limitations

Description indicates focus on X posting and monetization; other platforms not specified
Limited source material; details on endpoints and configuration are not provided

Captured live from the server via tools/list.

excalibur_check_balance

Check a patron's credit balance at this operator. This is the patron's spending balance — credits purchased via Lightning for tool calls at this operator. For the operator's own balance at the Authority (needed to certify patron purchases), use authority_check_balance instead. Free — no credits required. Proof of npub ownership is required to prevent anyone-with-the-registry from enumerating balances. Args: npub: The Nostr public key (npub1...) whose balance to check. dpop_token: A kind-27235 Nostr event signed by npub for this tool.

Parameters2

npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_purchase_credits

Buy credits via Bitcoin Lightning. Creates a Lightning invoice. Pay it with any Lightning wallet, then call check_payment to confirm. Proof of npub ownership is required so credits land in the correct ledger. Free — no credits required to call. Args: npub: The Nostr public key (npub1...) the credits will fund. dpop_token: A kind-27235 Nostr event signed by npub for this tool. amount_sats: Satoshis to purchase (default 1000).

Parameters3

npub	string	required
dpop_token	string	required
amount_sats	integer	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    },
    "amount_sats": {
      "default": 1000,
      "type": "integer"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_check_payment

Check the payment status of a Lightning invoice. Call after paying the invoice from purchase_credits. Free — no credits required. Proof of npub ownership is required to prevent credit-grant front-running by an observer of the invoice ID. Args: invoice_id: The invoice ID returned by purchase_credits. npub: The Nostr public key (npub1...) that purchased the invoice. dpop_token: A kind-27235 Nostr event signed by npub for this tool.

Parameters3

invoice_id	string	required
npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "invoice_id": {
      "type": "string"
    },
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "invoice_id",
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_restore_credits

Credit a patron's ledger from a BTCPay-settled invoice. **RESTRICTED to the operator** — the operator owns the books and is the only party who can issue a manual credit grant. Patrons who believe they paid but never got credits must escalate to the operator's support, who then invokes this tool on their behalf. Use cases: cold-start vault races during check_payment, ncred delivery hiccups, patrons closing Top-Off sheets before settle, any infrastructure incident that left an invoice settled at BTCPay but uncredited on the operator's ledger. Idempotent — if the invoice is already credited (in the patron's ``credited_invoices``), returns success with credits_granted=0. Args: invoice_id: The BTCPay invoice ID to verify and credit. patron_npub: The patron's npub whose ledger receives the grant. dpop_token: A kind-27235 Nostr event signed by the OPERATOR's nsec for this tool. Patron proofs are rejected.

Parameters3

invoice_id	string	required
patron_npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "invoice_id": {
      "type": "string"
    },
    "patron_npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "invoice_id",
    "patron_npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_account_statement

Generate a patron's account statement at this operator. Returns the patron's purchase history, active credit tranches, per-tool usage breakdown, and recent daily usage logs. This is the patron's spending account — not the operator's Authority tax balance. Free — no credits consumed. Proof of npub ownership is required to prevent statement-scraping of arbitrary patrons. Args: npub: The patron's Nostr public key (npub1...). dpop_token: A kind-27235 Nostr event signed by npub for this tool. days: Number of days of daily usage history to include (default 30).

Parameters3

npub	string	required
dpop_token	string	required
days	integer	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    },
    "days": {
      "default": 30,
      "type": "integer"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_account_statement_infographic

Generate a visual SVG infographic of your account statement. Returns the same data as account_statement, rendered as a dark-themed SVG graphic with balance hero, metrics cards, health gauge, tranche table, and tool usage breakdown. Costs 1 api_sat per call. Proof is verified by ``debit_or_deny`` before any cost is incurred. Args: npub: The Nostr public key (npub1...) whose statement to render. dpop_token: A kind-27235 Nostr event signed by npub for this tool. days: Number of days of daily usage history to include (default 30).

Parameters3

npub	string	required
dpop_token	string	required
days	integer	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    },
    "days": {
      "default": 30,
      "type": "integer"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_service_status

Check the health and configuration of this service. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_get_operator_onboarding_status

Report this operator's configuration readiness. Shows which operator settings are configured, which are missing, and how to deliver each missing value. For patron-level credential status, use get_patron_onboarding_status instead. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_get_patron_onboarding_status

Report a patron's credential readiness for this operator. For set-once services (eXcalibur, TheBrain), shows which patron secrets are configured and which are missing. For dynamic/OAuth2 services (Schwab), reports that no patron credentials are needed. Free. Proof of npub ownership is required because credential presence is sensitive information about the patron's setup. Args: patron_npub: The patron's Nostr public key (npub1...). dpop_token: A kind-27235 Nostr event signed by patron_npub for this tool.

Parameters2

patron_npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "patron_npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "patron_npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_session_status

Check operator readiness. Returns the operator lifecycle state and clear guidance on what to do next. Free. Lifecycle states: - ready: Operator is warm and fully operational — vault AND pricing model verified. Proceed with tool calls. - warming_up: Operator is initializing (cold start). Try a tool call — it will warm up on demand. - misconfigured: Persistence rejected a query with a permanent SQL error (permission denied, missing relation). Paid tools will fail until the operator repairs the database — retrying does not help. - not_registered: Operator has no Authority relationship yet. Call register_operator first. - no_identity: Operator nsec is not configured. Deployment issue. Args: patron_npub: Optional. If supplied, the response includes an ``upstream_oauth`` block with the patron's stored OAuth token expiry (runtime-derived from vault state) so a client can refresh proactively rather than reactively after a stale-token failure.

Parameters1

patron_npub

string

optional

Raw schema

{
  "type": "object",
  "properties": {
    "patron_npub": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_request_credential_channel

Open a Secure Courier channel for credential delivery. This is the CREDENTIAL-DELIVERY flow — use it to hand over a service secret (API keys, tokens). To merely prove you control an npub (the usual answer to a ``proof_required`` error), use ``request_npub_proof`` instead. Note: dynamic/OAuth2 services (e.g. Schwab) need NO couriered secret — check ``service_status`` first. Sends a welcome DM with a credential template. The recipient must read the DM in their Nostr client, fill in the fields, and reply manually. **This is a human-in-the-loop flow.** After calling this tool, STOP and tell the user what to do. Wait for the user to confirm they have replied before calling ``receive_credentials``. Do NOT poll or retry — each ``receive_credentials`` call destructively drains the relay mailbox. Args: sender_npub: Required. The npub to send the template to. service: Required. The credential service name (e.g., from get_operator_onboarding_status or get_patron_onboarding_status). Free.

Parameters2

sender_npub	string	optional
service	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "sender_npub": {
      "default": "",
      "type": "string"
    },
    "service": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_receive_credentials

Pick up credentials from the Secure Courier. Completes the CREDENTIAL-DELIVERY flow (the ownership-proof counterpart is ``receive_npub_proof``). **Call this only after the user confirms they have replied.** Deterministic, one-shot retrieval: name the response you want with ``(sender_npub, service, dpop_token)`` and the tool drains ONLY the rendezvous relay that channel was pinned to. Every popped DM with the wrong session phrase is deleted and its sender is NACK'd; the first DM with the matching phrase is accepted (ACK'd) and the scan stops. If none match, the queue is drained and a ``courier_not_found`` result is returned. Do NOT poll, loop, or retry. If a credential_card (ncred1...) is provided, it is redeemed directly without any relay access (dpop_token not required for that path). On success, the payment processor client is reinitialized from the new credentials — no server restart needed. Args: sender_npub: Required. The npub that sent the credentials. service: Required. The credential service name (must match the service used in request_credential_channel). dpop_token: Required. The session phrase returned by request_credential_channel for this exact channel. credential_card: Optional. An ncred1... card to redeem directly (bypasses the relay drain; dpop_token not needed). Free.

Parameters4

sender_npub	string	optional
service	string	optional
dpop_token	string	optional
credential_card	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "sender_npub": {
      "default": "",
      "type": "string"
    },
    "service": {
      "default": "",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    },
    "credential_card": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_forget_credentials

Delete vaulted credentials for a specific service and npub. For operator credentials, pass the operator's own npub. For patron credentials, pass the patron's npub. Always requires proof of npub ownership — a deletion is as destructive as a write. Args: service: The credential service to forget. npub: The Nostr public key (npub1...) whose credentials to forget. dpop_token: A kind-27235 Nostr event signed by npub for this tool. Free.

Parameters3

service	string	required
npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "service": {
      "type": "string"
    },
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "service",
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_update_patron_credential

Add or update a single patron credential field. Merges into existing stored credentials without affecting other fields. Useful for setting an account identifier after OAuth, changing a default brain, etc. Free. Proof of npub ownership is required — this is a write to the patron's sensitive credential vault. Args: npub: The patron's Nostr public key (npub1...). dpop_token: A kind-27235 Nostr event signed by npub for this tool. field: The credential field name to set. value: The value to store.

Parameters4

npub	string	required
dpop_token	string	required
field	string	required
value	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    },
    "field": {
      "type": "string"
    },
    "value": {
      "type": "string"
    }
  },
  "required": [
    "npub",
    "dpop_token",
    "field",
    "value"
  ],
  "additionalProperties": false
}

excalibur_delete_patron_credential

Remove a single patron credential field. Deletes one field from stored credentials without affecting other fields. Free. Proof of npub ownership is required — this is a write to the patron's sensitive credential vault. Args: npub: The patron's Nostr public key (npub1...). dpop_token: A kind-27235 Nostr event signed by npub for this tool. field: The credential field name to remove.

Parameters3

npub	string	required
dpop_token	string	required
field	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    },
    "field": {
      "type": "string"
    }
  },
  "required": [
    "npub",
    "dpop_token",
    "field"
  ],
  "additionalProperties": false
}

excalibur_get_patron_credential_fields

List stored patron credential field names (not values). Returns the names of fields stored for a patron. Values are never exposed — use this to verify which fields are configured. Free. Proof of npub ownership is required: the list of configured fields is itself sensitive (reveals which integrations a patron has set up). Args: npub: The patron's Nostr public key (npub1...). dpop_token: A kind-27235 Nostr event signed by npub for this tool.

Parameters2

npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_begin_oauth

Start the OAuth2 authorization flow. Returns an authorization URL. Open it in a browser to log in and authorize. Then call ``check_oauth_status`` with the same npub to complete. Free. Proof of npub ownership is required so an observer cannot DOS your account by initiating OAuth flows in your name. Do NOT call this pre-emptively. If a session may still be valid, attempt the live tool call first and only begin OAuth when it fails with ``upstream_auth_refresh_needed``. A 'pending' ``check_oauth_status`` is not evidence that an existing session has lapsed. Args: npub: Your DPYC patron npub (npub1...). dpop_token: A kind-27235 Nostr event signed by npub for this tool.

Parameters2

npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_check_oauth_status

Check whether the OAuth2 authorization flow has completed. Call after opening the authorization URL from ``begin_oauth`` and completing the login in your browser. Free. Proof of npub ownership is required: OAuth status exposes which upstream services a patron has connected. A 'pending' result here does NOT prove an existing session has lapsed — it only reports this authorization attempt. To find out whether a session still works, attempt the live call; fall back to ``begin_oauth`` only on an explicit ``upstream_auth_refresh_needed`` error. Args: npub: The same Nostr public key (npub1...) used in begin_oauth. dpop_token: A kind-27235 Nostr event signed by npub for this tool.

Parameters2

npub	string	required
dpop_token	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "type": "string"
    }
  },
  "required": [
    "npub",
    "dpop_token"
  ],
  "additionalProperties": false
}

excalibur_request_npub_proof

Request npub ownership proof from a patron via Nostr DM. This is the npub-OWNERSHIP-PROOF flow — use it when a call returns ``proof_required``. It proves the caller controls an npub; it does NOT deliver any service secret. To hand an operator its API keys or OAuth secrets, use ``request_credential_channel`` instead. Sends a challenge DM that the patron must sign and reply to using their Nostr client. **This is a human-in-the-loop flow.** After calling this tool, STOP and tell the user to check their Nostr client and reply to the challenge. Wait for the user to confirm they have replied before calling ``receive_npub_proof``. Do NOT poll or retry — each ``receive_npub_proof`` call destructively drains the relay mailbox. **Returns** a ``dpop_token`` — the demonstrated-proof-of-possession token that the calling application MUST remember and pass as the ``dpop_token`` parameter on every subsequent paid tool call. The MCP does not retain this value across restarts. **Lifecycle:** The cached proof expires after the patron's chosen duration. When it expires, call ``request_npub_proof`` again for a fresh challenge, then wait for the user, then call ``receive_npub_proof``. Free. Args: patron_npub: Required. The patron's npub to request proof from.

Parameters1

patron_npub

string

optional

Raw schema

{
  "type": "object",
  "properties": {
    "patron_npub": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_receive_npub_proof

Receive npub ownership confirmation from a patron. Completes the npub-OWNERSHIP-PROOF flow (the credential-delivery counterpart is ``receive_credentials``). **Call this only after the user confirms they have replied.** Deterministic, one-shot retrieval: name the response with ``(patron_npub, dpop_token)`` — the ``dpop_token`` being the value returned by ``request_npub_proof``. The tool drains ONLY the pinned rendezvous relay that challenge was published on, stopping at the DM whose phrase matches. Mismatched DMs are deleted and NACK'd (without revealing the expected phrase). If called before the user replies, their message will never be found. Do NOT poll, loop, or retry. The signed DM itself proves npub ownership (the patron's nsec signed it). On success, returns the ``dpop_token`` — the same token. The calling application MUST remember it and pass it as the ``dpop_token`` parameter on every subsequent paid tool call. The proof (a hash of the token) is stored in the vault keyed by that hash — the MCP never stores the raw token itself. Free. Args: patron_npub: Required. The patron's npub to receive proof from. dpop_token: Required. The dpop_token returned by request_npub_proof.

Parameters2

patron_npub	string	optional
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "patron_npub": {
      "default": "",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_check_proof_status

Check whether a previously-cached dpop_token is still valid. Mirrors ``check_oauth_status`` for the npub-proof flow: a calling agent can ask "will my next paid call accept this dpop_token?" before burning credits on a guaranteed failure. Free, no side effects — does not evict the cache or touch relays. Args: patron_npub: Required. The patron's npub (npub1...). dpop_token: Required. The dpop_token phrase returned by ``request_npub_proof`` / ``receive_npub_proof``.

Parameters2

patron_npub	string	optional
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "patron_npub": {
      "default": "",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_oracle_how_to_join

Get DPYC onboarding instructions from the Oracle. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_oracle_get_tax_rate

Get the current DPYC certification tax rate. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_oracle_lookup_member

Look up a DPYC community member by npub. Free.

Parameters1

npub

string

required

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    }
  },
  "required": [
    "npub"
  ],
  "additionalProperties": false
}

excalibur_oracle_about

Describe the DPYC ecosystem via the Oracle. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_oracle_network_advisory

Get active network advisories from the Oracle. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_check_authority_balance

Check this operator's tax balance at the Authority. Returns the sats available for certifying patron credit purchases. When this balance reaches zero, patron top-ups cannot be certified and the operator must call purchase_credits on the Authority. This is the operator's own funding — not a patron balance. Free.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_get_pricing_model

Get the active pricing model for this operator. Free. If no model exists, self-initializes a scaffold with all registered tools at 0 sats. No economic data from code.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_set_pricing_model

Set the active pricing model. RESTRICTED to operator. Requires a valid proof (Schnorr-signed kind-27235 event) proving the caller holds the operator's nsec.

Parameters2

model_json	string	required
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "model_json": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "model_json"
  ],
  "additionalProperties": false
}

excalibur_reset_pricing_model

Erase all pricing models and restore a viable default. Deletes every stored model, then self-initializes a fresh one from the tool registry — all tools at 0 sats with proper UUIDs. Returns the new model. RESTRICTED to operator — requires proof (nsec-signed).

Parameters1

dpop_token

string

optional

Raw schema

{
  "type": "object",
  "properties": {
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_request_adoption

Ask a chosen Authority to adopt this operator (deferred courtship). RESTRICTED to the operator — requires proof the caller controls this operator's npub. Resolves the Authority's MCP endpoint from the community registry, mints an inline ownership proof with this operator's nsec, and delivers the request MCP-to-MCP. The Authority records it as pending; its owner approves on their own time. Poll ``adoption_status`` for progress; the operator flips to ``ready`` once the Authority provisions it. Args: authority_npub: npub of the Authority to request adoption from. dpop_token: operator-npub ownership proof (inline kind-27235 or cached token). service_url: this operator's MCP endpoint (advertised to the Authority). note: optional message for the Authority owner.

Parameters4

authority_npub	string	required
dpop_token	string	optional
service_url	string	optional
note	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "authority_npub": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    },
    "service_url": {
      "default": "",
      "type": "string"
    },
    "note": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "authority_npub"
  ],
  "additionalProperties": false
}

excalibur_adoption_status

Check this operator's adoption-request status at a chosen Authority. Free. Polls the Authority MCP-to-MCP for the status of this operator's request (pending / approved / rejected / provisioned).

Parameters2

authority_npub	string	required
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "authority_npub": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "authority_npub"
  ],
  "additionalProperties": false
}

excalibur_restore_neon_schema

Re-run ``ensure_schema()`` on every NeonVault this operator uses. Diagnostic / recovery tool for the case where the Neon HTTP SQL API is returning persistent 4xx errors and the operator suspects the schema isn't there or grants are wrong. Idempotent — uses ``CREATE TABLE IF NOT EXISTS`` so a successful re-run is harmless. Returns the per-step result. If any step raises, surfaces the Neon error message inline (0.31.0 reads the SQL error body that earlier wheels swallowed behind ``raise_for_status``). RESTRICTED to operator — requires proof (nsec-signed).

Parameters1

dpop_token

string

optional

Raw schema

{
  "type": "object",
  "properties": {
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_list_canonical_identities

Return canonical (tool_id, mcp_name, …) for every registered tool. The authoritative source for any client (Studio, agents, FE) that needs to know how this MCP identifies its tools. Reconcile uses this output to UUID-join against the stored pricing model — no name-based UUID derivation, no guessing. If the operator renames a function or rebrands a slug, the mcp_name in this output changes but tool_id stays. That's the whole point of the canonical-UUID design. Free, no side effects.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_get_nostr_profile

Read an npub's public Nostr profile (NIP-01 kind-0 metadata). Free, no proof — the data is already public on relays. Returns the latest metadata fields (name, display_name, about, picture, banner, nip05, website, lud16) or an empty profile if none is published.

Parameters1

npub

string

optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_publish_nostr_profile

Publish a CLIENT-SIGNED kind-0 profile to relays for an npub. The wheel never holds a patron nsec. The frontend signs the kind-0 metadata event with the patron's session key or a NIP-07 extension and passes the signed event (JSON) here; the wheel verifies the signature matches the npub, then relays it to public relays. The signature is the authorization — no proof token, no key custody. Free. Args: npub: The patron's Nostr public key the event must be signed by. signed_event: A JSON-encoded, client-signed kind-0 event.

Parameters2

npub	string	optional
signed_event	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "default": "",
      "type": "string"
    },
    "signed_event": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_check_price

Preview the effective cost of a tool call. Shows the base cost and any constraint effects (discounts, free trials, surge pricing). Free — no credits required. Args: tool_id: Either the tool's UUID (from the pricing model) or a bare capability string (e.g. ``"deal_scenario"``). FE callers usually have the capability name; this resolves both so the FE doesn't need to derive UUIDs locally. tool_kwargs: Optional JSON object with tool call parameters for ad valorem / categorical-multiplier pricing preview (e.g. '{"amount_sats": 5000}' or '{"difficulty": "sovereign", "mode": "live"}').

Parameters4

tool_id	string	required
npub	string	optional
dpop_token	string	optional
tool_kwargs	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "tool_id": {
      "type": "string"
    },
    "npub": {
      "default": "",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    },
    "tool_kwargs": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "tool_id"
  ],
  "additionalProperties": false
}

excalibur_list_constraint_types

List all available constraint types and their parameter schemas. Returns the type, category, description, and parameter specs for every constraint that can be used in a pricing pipeline. Free — no credits required.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_mint_coupon

Create a new operator-owned discount coupon. Args: name: The catchy code patrons type to redeem (operator-scoped uniqueness). discount_percent: Percentage off the base price (0-100). valid_from: ISO-8601 datetime when the coupon becomes active. valid_until: ISO-8601 datetime when the coupon expires. uses_per_patron: How many tool calls one patron can claim the discount on (default 1; pass null/None for unlimited within the window). total_uses: Aggregate cap across all patrons (default None = unlimited). Returns the new coupon row. RESTRICTED to operator — requires proof (nsec-signed kind-27235 or cached dpop_token token).

Parameters7

name	string	required
discount_percent	number	required
valid_from	string	required
valid_until	string	required
uses_per_patron	any	optional
total_uses	any	optional
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "name": {
      "type": "string"
    },
    "discount_percent": {
      "type": "number"
    },
    "valid_from": {
      "type": "string"
    },
    "valid_until": {
      "type": "string"
    },
    "uses_per_patron": {
      "anyOf": [
        {
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": 1
    },
    "total_uses": {
      "anyOf": [
        {
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "name",
    "discount_percent",
    "valid_from",
    "valid_until"
  ],
  "additionalProperties": false
}

excalibur_list_coupons

List every coupon this operator has minted (newest first). Each row carries the current ``times_redeemed`` counter — the Studio renders a progress bar from this against ``total_uses``. RESTRICTED to operator — requires proof.

Parameters1

dpop_token

string

optional

Raw schema

{
  "type": "object",
  "properties": {
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_update_coupon

Patch a coupon's editable fields. Pass only the fields you want to change. To set a cap to unlimited (NULL in the schema), pass ``clear_uses_per_patron=true`` or ``clear_total_uses=true``. Renaming the code is allowed — existing patron redemption rows survive (they key on coupon id). RESTRICTED to operator — requires proof.

Parameters10

coupon_id	string	required
name	any	optional
discount_percent	any	optional
valid_from	any	optional
valid_until	any	optional
uses_per_patron	any	optional
total_uses	any	optional
clear_uses_per_patron	boolean	optional
clear_total_uses	boolean	optional
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "coupon_id": {
      "type": "string"
    },
    "name": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "discount_percent": {
      "anyOf": [
        {
          "type": "number"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "valid_from": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "valid_until": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "uses_per_patron": {
      "anyOf": [
        {
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "total_uses": {
      "anyOf": [
        {
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "clear_uses_per_patron": {
      "default": false,
      "type": "boolean"
    },
    "clear_total_uses": {
      "default": false,
      "type": "boolean"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "coupon_id"
  ],
  "additionalProperties": false
}

excalibur_delete_coupon

Delete a coupon. Cascades to all patron redemptions. Any chain step referencing the deleted coupon_id becomes a no-op (the constraint returns neutral on unknown ids) — the Studio surfaces orphan references as warnings. RESTRICTED to operator — requires proof.

Parameters2

coupon_id	string	required
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "coupon_id": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "coupon_id"
  ],
  "additionalProperties": false
}

excalibur_redeem_coupon

Claim a coupon by its name (the code the operator shared). Looks up the operator's coupon by ``code``, validates the window and total cap, and records a per-patron redemption row. Subsequent paid tool calls on this MCP auto-apply the discount until ``uses_per_patron`` is exhausted. Free — no credits required. Requires proof of ``npub``. Idempotent: redeeming the same code twice returns the existing redemption.

Parameters3

npub	string	required
code	string	required
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "code": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "npub",
    "code"
  ],
  "additionalProperties": false
}

excalibur_list_my_coupons

List the coupons this patron has redeemed on this operator. Returns both active and exhausted redemptions with a per-row ``status`` (``active`` / ``window_closed`` / ``patron_limit`` / ``total_limit``). Free — requires proof of ``npub``.

Parameters2

npub	string	required
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "npub"
  ],
  "additionalProperties": false
}

excalibur_forget_coupon

Remove a coupon from this patron's redemption list. Cosmetic only — the coupon itself still exists at the operator, and the patron can re-redeem the same code later while the window allows. Free — requires proof of ``npub``.

Parameters3

npub	string	required
coupon_id	string	required
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "type": "string"
    },
    "coupon_id": {
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "npub",
    "coupon_id"
  ],
  "additionalProperties": false
}

excalibur_notarize_ledger

Build a Merkle tree of all patron balances and submit the root to Bitcoin via OpenTimestamps. Operator-only background task. Bitcoin confirmation takes 1-6 hours. Free — no credits required.

Parameters

No parameters.

Raw schema

{
  "type": "object",
  "properties": {},
  "additionalProperties": false
}

excalibur_get_notarization_proof

Generate a Merkle inclusion proof that a patron's balance was included in a Bitcoin-notarized snapshot. Args: notarization_id: The notarization record ID. npub: The patron's Nostr public key (npub1...).

Parameters2

notarization_id	string	required
npub	string	required

Raw schema

{
  "type": "object",
  "properties": {
    "notarization_id": {
      "type": "string"
    },
    "npub": {
      "type": "string"
    }
  },
  "required": [
    "notarization_id",
    "npub"
  ],
  "additionalProperties": false
}

excalibur_list_notarizations

List recent Bitcoin notarization records. Args: limit: Maximum records to return (default 20). status: Optional filter (e.g., 'submitted', 'confirmed').

Parameters2

limit	integer	optional
status	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "limit": {
      "default": 20,
      "type": "integer"
    },
    "status": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_post_tweet

Post a text tweet with markdown formatting converted to Unicode rich text. Accepts standard markdown inline formatting and converts it to Unicode Mathematical Alphanumeric Symbols that render as styled text on X: **bold** -> bold *italic* -> italic ***bold italic*** -> bold italic `monospace` -> monospace Args: text: Tweet content with optional markdown formatting. npub: Your DPYC patron Nostr public key (npub1...) for credit attribution.

Parameters3

text	string	required
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "text": {
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "text"
  ],
  "additionalProperties": false
}

excalibur_get_x_profile

Fetch the connected X account's handle and name for this patron (free). Uses the patron's vaulted X OAuth token to call X's ``/users/me``. Returns ``{connected: true, username, name, profile_image_url}`` when connected, or the OAuth situation (``connected`` absent) when X isn't linked yet. Used to show the real @handle on the editor's tweet-card preview.

Parameters2

npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_post_tweet_image

Post a tweet with a hero banner image to X/Twitter. Provide either an image_url (fetched and attached) or banner_svg (rendered to PNG and attached). Text supports the same markdown formatting as post_tweet. Args: text: Tweet content with optional markdown formatting. image_url: URL of an image to attach to the tweet. banner_svg: Self-contained SVG markup string, converted to PNG. npub: Your DPYC patron Nostr public key (npub1...) for credit attribution.

Parameters5

text	string	required
image_url	string	optional
banner_svg	string	optional
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "text": {
      "type": "string"
    },
    "image_url": {
      "default": "",
      "type": "string"
    },
    "banner_svg": {
      "default": "",
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "text"
  ],
  "additionalProperties": false
}

excalibur_create_post

Store a new post (draft or scheduled). Returns its ``post_id``. Args: doc: The editable Doc (blocks + flags + voice + bans + schedule). text_cache: Composed text (blocks joined) for scheduler + list excerpts. publish_at: ISO-8601 first/next publish time; required when status='scheduled'. recurrence: ``{"freq": "daily|weekly|monthly", "interval": n}`` or null. cease_at: ISO-8601 stop time for recurrence; null = open-ended. status: ``draft`` or ``scheduled``. client_req_id: Idempotency key — re-sending the same id returns the same post without a second charge. title: Optional human label for the post; the list falls back to the first body line when it is blank. npub: Your DPYC patron Nostr public key for credit attribution.

Parameters11

doc	object	required
text_cache	string	optional
publish_at	any	optional
recurrence	any	optional
cease_at	any	optional
status	string	optional
client_req_id	string	optional
tweet_url	string	optional
title	string	optional
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "doc": {
      "additionalProperties": true,
      "type": "object"
    },
    "text_cache": {
      "default": "",
      "type": "string"
    },
    "publish_at": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "recurrence": {
      "anyOf": [
        {
          "additionalProperties": true,
          "type": "object"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "cease_at": {
      "anyOf": [
        {
          "type": "string"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "status": {
      "default": "draft",
      "type": "string"
    },
    "client_req_id": {
      "default": "",
      "type": "string"
    },
    "tweet_url": {
      "default": "",
      "type": "string"
    },
    "title": {
      "default": "",
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "doc"
  ],
  "additionalProperties": false
}

excalibur_get_post

Read one stored post by id (owner-scoped).

Parameters3

post_id	string	required
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "post_id": {
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "post_id"
  ],
  "additionalProperties": false
}

excalibur_list_posts

List your stored posts, server-side sorted, filtered, and offset-paginated. Optional ``status`` filter — a single status or a comma-separated set (e.g. ``draft,scheduled``), matched as set membership. ``sort_col`` is one of ``created|updated|status|scheduled`` (default ``created``); ``sort_dir`` is ``asc|desc``. ``search`` is a case-insensitive regular expression matched against the post text. ``date_from``/``date_to`` (``YYYY-MM-DD``, end-inclusive) bound the ``date_field`` column, one of ``created|updated|scheduled|sent`` (default ``created``). ``template_id`` filters to the sent occurrences a recurring template fired. ``page`` is 0-indexed; ``page_size`` is 1..100. Each row carries ``is_recurring``, ``has_dynamic``, and ``template_id`` (set on sent occurrences). Returns ``{posts:[…], total, page, page_size}`` reflecting the filtered set.

Parameters12

status	string	optional
sort_col	string	optional
sort_dir	string	optional
page	integer	optional
page_size	integer	optional
search	string	optional
date_from	string	optional
date_to	string	optional
date_field	string	optional
template_id	string	optional
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "status": {
      "default": "",
      "type": "string"
    },
    "sort_col": {
      "default": "created",
      "type": "string"
    },
    "sort_dir": {
      "default": "desc",
      "type": "string"
    },
    "page": {
      "default": 0,
      "type": "integer"
    },
    "page_size": {
      "default": 25,
      "type": "integer"
    },
    "search": {
      "default": "",
      "type": "string"
    },
    "date_from": {
      "default": "",
      "type": "string"
    },
    "date_to": {
      "default": "",
      "type": "string"
    },
    "date_field": {
      "default": "created",
      "type": "string"
    },
    "template_id": {
      "default": "",
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_update_post

Patch a stored post. ``patch`` may set ``doc, publish_at, recurrence, cease_at, status`` (omit a field to leave it unchanged). ``text_cache`` is written when supplied (alongside a doc change). ``client_req_id`` dedupes debounced autosave retries — a repeat is a no-op with no second charge.

Parameters6

post_id	string	required
patch	object	required
text_cache	string	optional
client_req_id	string	optional
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "post_id": {
      "type": "string"
    },
    "patch": {
      "additionalProperties": true,
      "type": "object"
    },
    "text_cache": {
      "default": "",
      "type": "string"
    },
    "client_req_id": {
      "default": "",
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "post_id",
    "patch"
  ],
  "additionalProperties": false
}

excalibur_delete_post

Delete a stored post. Default is a soft delete (``status='archived'``); pass ``hard=True`` to remove the row permanently.

Parameters4

post_id	string	required
hard	boolean	optional
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "post_id": {
      "type": "string"
    },
    "hard": {
      "default": false,
      "type": "boolean"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "post_id"
  ],
  "additionalProperties": false
}

excalibur_list_snippets

List your saved post snippets, server-side sorted, filtered, and offset-paginated. ``sort_col`` is one of ``favorite|created|updated|name`` (default ``favorite``); ``sort_dir`` is ``asc|desc``. ``search`` is a case-insensitive regular expression matched against the snippet name or body. ``date_from``/``date_to`` (``YYYY-MM-DD``, end-inclusive) bound the ``date_field`` column, one of ``created|updated`` (default ``created``). ``page`` is 0-indexed; ``page_size`` is 1..200. Free, owner-scoped. Returns ``{snippets:[…], total, page, page_size}`` reflecting the filtered set.

Parameters10

sort_col	string	optional
sort_dir	string	optional
page	integer	optional
page_size	integer	optional
search	string	optional
date_from	string	optional
date_to	string	optional
date_field	string	optional
npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "sort_col": {
      "default": "favorite",
      "type": "string"
    },
    "sort_dir": {
      "default": "desc",
      "type": "string"
    },
    "page": {
      "default": 0,
      "type": "integer"
    },
    "page_size": {
      "default": 25,
      "type": "integer"
    },
    "search": {
      "default": "",
      "type": "string"
    },
    "date_from": {
      "default": "",
      "type": "string"
    },
    "date_to": {
      "default": "",
      "type": "string"
    },
    "date_field": {
      "default": "created",
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_get_snippet

Read one of your saved snippets by id (full row incl. ``doc`` block document). Free and owner-scoped. Returns ``{"success": true, "snippet": …}`` or ``snippet_not_found``.

Parameters3

snippet_id	string	required
npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "snippet_id": {
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "snippet_id"
  ],
  "additionalProperties": false
}

excalibur_save_snippet

Save a reusable post snippet (opening/footer/CTA). Omit ``snippet_id`` to create a new one; pass it to update an existing snippet in place (name/text/ favorite/doc). On update only the fields you pass change — omit ``favorite`` (leave it null) to keep it as-is, so a doc-only patch (e.g. toggling a snippet dynamic) doesn't reset it. ``doc`` is the same block/flag document a post carries, so the editor is identical for both. Free and owner-scoped. Returns ``{"success": true, "snippet": …}``.

Parameters7

name	string	optional
text	string	optional
snippet_id	string	optional
favorite	any	optional
doc	any	optional
npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "name": {
      "default": "",
      "type": "string"
    },
    "text": {
      "default": "",
      "type": "string"
    },
    "snippet_id": {
      "default": "",
      "type": "string"
    },
    "favorite": {
      "anyOf": [
        {
          "type": "boolean"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "doc": {
      "anyOf": [
        {
          "additionalProperties": true,
          "type": "object"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_delete_snippet

Delete one of your saved snippets by id. Free and owner-scoped.

Parameters3

snippet_id	string	required
npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "snippet_id": {
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "snippet_id"
  ],
  "additionalProperties": false
}

excalibur_get_voice

Read your saved writing Voice — a profile blurb plus a list of "banned construction" chips (``{text, on}``) the editor passes to ``refine_post_region``. Owner-scoped; priced by the operator's pricing model (use ``check_price``). When you have not saved a Voice yet this returns an empty one (``{"voice": {"profile": "", "bans": []}}``) so the editor can seed its own defaults, not an error.

Parameters2

npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_save_voice

Save your writing Voice (replaces the previous one — it is a per-npub singleton). ``profile`` is free text. ``bans`` is a list of ``{text, on}`` objects: ``text`` is the construction to avoid, ``on`` whether it is an active constraint. Blank/duplicate entries are dropped server-side. Owner-scoped; priced by the operator's pricing model (use ``check_price``). Returns ``{"success": true, "voice": {...}}``.

Parameters4

profile	string	optional
bans	any	optional
npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "profile": {
      "default": "",
      "type": "string"
    },
    "bans": {
      "anyOf": [
        {
          "items": {},
          "type": "array"
        },
        {
          "type": "null"
        }
      ],
      "default": null
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_refine_post_region

Refine a flagged region of a post with Claude — server-side. The operator's Anthropic key stays in the vault and never leaves the server. Send the flagged ``region``, the surrounding ``full_text``, an optional ``instruction`` (what to change), and the editor's ``voice`` profile + ``bans`` (JSON array or comma list of banned constructions). Returns ``{"success": true, "suggestions": [...3 strings...]}``. Paid: the AI cost is metered as a tollbooth fare. The fare is refunded if no Anthropic key is configured or the upstream call returns nothing. Args: region: The flagged span to rewrite. full_text: The whole tweet, for context. instruction: What the editor wants changed (optional). voice: Voice-profile text fed to the model (optional). bans: Banned constructions — JSON array or comma-separated (optional). npub: Your DPYC patron npub for credit billing.

Parameters7

region	string	required
full_text	string	optional
instruction	string	optional
voice	string	optional
bans	string	optional
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "region": {
      "type": "string"
    },
    "full_text": {
      "default": "",
      "type": "string"
    },
    "instruction": {
      "default": "",
      "type": "string"
    },
    "voice": {
      "default": "",
      "type": "string"
    },
    "bans": {
      "default": "",
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "region"
  ],
  "additionalProperties": false
}

excalibur_resolve_dynamic_block

Start resolving a dynamic post block with Claude — returns a CLAIM CHECK. A dynamic block's ``prompt`` is run by Claude (with web search + web fetch for live data) and woven into the surrounding post ``context`` in the author's ``voice``. The author's instruction governs length — there is no character cap (X supports long-form posts). The operator's Anthropic key stays in the vault and never leaves the server. Because that work (paginated fetches + generation) can outlast a client timeout, this returns immediately with a **claim check** instead of the text: ``{"success": true, "claim_check": "...", "status": "pending", "poll_after_seconds": N}``. Redeem it with the free companion ``fetch_dynamic_block(claim_check)`` until ``status == "done"`` (then read ``result.text``). (The scheduler resolves blocks directly server-side at fire time and does not use this tool.) Paid: the AI cost is metered as a tollbooth fare on THIS start call, refunded if no Anthropic key is configured or the job ultimately fails. Args: prompt: The dynamic block's prompt to run. context: The surrounding composed post (may contain the ⟨HERE⟩ marker). voice: Voice-profile text fed to the model (optional). bans: Banned constructions — JSON array or comma-separated (optional). allowed_domains: Author allowlist for web_fetch — JSON array or comma-separated. Blank = fetch any URL the prompt references. max_fetches: Author budget for web lookups (search + fetch), 1..25. runtime_limit_seconds: Author's time budget (clamped 60..900). Sets the job's runtime ceiling and the poll cadence (first poll ~75% of it), and is available to the operator's pricing model for ad-valorem fares. npub: Your DPYC patron npub for credit billing.

Parameters9

prompt	string	required
context	string	optional
voice	string	optional
bans	string	optional
allowed_domains	string	optional
max_fetches	integer	optional
runtime_limit_seconds	integer	optional	Author's time budget for this block in seconds (60–900). Bounds how long the job may run AND sets the poll cadence; the operator may price it ad valorem.
npub	string	optional	Required. Your Nostr public key (npub1...) for credit billing.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "prompt": {
      "type": "string"
    },
    "context": {
      "default": "",
      "type": "string"
    },
    "voice": {
      "default": "",
      "type": "string"
    },
    "bans": {
      "default": "",
      "type": "string"
    },
    "allowed_domains": {
      "default": "",
      "type": "string"
    },
    "max_fetches": {
      "default": 5,
      "type": "integer"
    },
    "runtime_limit_seconds": {
      "default": 210,
      "description": "Author's time budget for this block in seconds (60–900). Bounds how long the job may run AND sets the poll cadence; the operator may price it ad valorem.",
      "type": "integer"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...) for credit billing.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "prompt"
  ],
  "additionalProperties": false
}

excalibur_fetch_dynamic_block

Redeem a ``resolve_dynamic_block`` claim check (free, proof-gated). Poll this with the ``claim_check`` from ``resolve_dynamic_block`` until ``status == "done"`` (the resolved fragment is ``result.text``). While the job runs it returns ``{"status": "running", "poll_after_seconds": N}``; on failure ``{"status": "error", ...}`` (the start fare is refunded); an unknown or aged-out claim returns ``{"status": "expired", ...}``. Owner-scoped — only the npub that started the job can redeem it. Also acts as the watchdog: a stalled job is re-kicked when polled.

Parameters3

claim_check	string	required
npub	string	optional	Required. Your Nostr public key (npub1...).
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "claim_check": {
      "type": "string"
    },
    "npub": {
      "default": "",
      "description": "Required. Your Nostr public key (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "required": [
    "claim_check"
  ],
  "additionalProperties": false
}

excalibur_process_scheduled_posts

Publish every due scheduled post (operator-only). Selects ``scheduled`` posts whose ``publish_at`` has arrived, posts each on behalf of its owner (billing the owner for ``post_tweet``), stamps ``last_sent_at``, and reschedules from ``recurrence`` or retires the post past ``cease_at``. Requires the operator's npub proof; the trigger itself is free. Returns ``{processed, posted, skipped, errors}``.

Parameters2

npub	string	optional	The OPERATOR's npub (npub1...); this tool is operator-only.
dpop_token	string	optional

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "default": "",
      "description": "The OPERATOR's npub (npub1...); this tool is operator-only.",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    }
  },
  "additionalProperties": false
}

excalibur_get_scheduler_log

Read recent scheduler-tick outcomes. Each ``process_scheduled_posts`` run — fired by the Cloudflare cron Worker or a manual trigger — records its summary. This surfaces them so the FE debug log can show what the Worker is doing: the per-tick heartbeat (proof it ran) and per-post outcomes (posted / skip+error reasons like ``insufficient_balance`` or ``oauth_token_expired``). Owner-scoped: the operator sees every tick in full; any other proven patron sees the global heartbeat (``processed`` count + ``run_at``) plus only the per-post entries for THEIR OWN posts. Free; npub proof required. Returns ``{runs:[{run_at, summary}], scope}``.

Parameters3

npub	string	optional	Your npub (npub1...).
dpop_token	string	optional
limit	integer	optional	How many recent runs to return (1..100).

Raw schema

{
  "type": "object",
  "properties": {
    "npub": {
      "default": "",
      "description": "Your npub (npub1...).",
      "type": "string"
    },
    "dpop_token": {
      "default": "",
      "type": "string"
    },
    "limit": {
      "default": 25,
      "description": "How many recent runs to return (1..100).",
      "type": "integer"
    }
  },
  "additionalProperties": false
}

README.md12 KBView on GitHub

eXcalibur MCP

Sword-swift posting of pretty tweets to X (Twitter) via AI agents, monetized with Bitcoin Lightning micropayments through the DPYC(TM) Tollbooth protocol.

eXcalibur is a FastMCP server that lets AI agents post to X (Twitter) with rich Unicode formatting and optional images. Patron authentication for X uses OAuth2 Authorization Code + PKCE -- no credentials appear in chat. Operator credentials (X app keys, BTCPay) arrive via human-in-the-loop Secure Courier and are stored in the operator's per-operator Neon vault schema. Tool calls are metered with Tollbooth DPYC(TM) pre-funded Lightning balances -- Don't Pester Your Customer.

Part of the DPYC(TM) Social Contract.

Getting Started

Connect via FastMCP Cloud -- no local install needed:

code

https://www.fastmcp.cloud/mcp/lonniev/excalibur-mcp

Step 1: Check Session

Call excalibur_session_status to see your current session state. If you have an active session with funded credits, you are ready to post.

Step 2: X OAuth2 + PKCE (Patron Credentials for X)

Get your Nostr npub -- use the dpyc-oracle's how_to_join() tool, or any Nostr client.
Call excalibur_begin_oauth(npub=<npub>) -- returns an authorize_url. Open the primary authorize_url (not a shortlink) in your browser and authorize the app on X.
Call excalibur_check_oauth_status(npub=<npub>) -- completes the code exchange, vaults the tokens, and activates your session.

Sessions are keyed by npub. Tokens are stored in the Neon vault and auto-refresh on expiry.

Step 3: Secure Courier (Operator Credentials)

Operator credentials (X OAuth2 app keys, BTCPay connection) are delivered via Secure Courier (service="excalibur-operator"). This is a human-in-the-loop flow: the operator consciously approves each credential delivery via their Nostr client. On receive_credentials, the relay DM is destructively drained -- credentials exist only in the Neon vault after receipt.

Credits Model

Tool calls cost api_sats per call. Credits have a tranche_lifetime -- each purchase creates a tranche that expires after the configured lifetime. Auth and balance tools are always free. Use excalibur_check_balance to see your balance and tranche expiry. Top up via excalibur_purchase_credits.

Available Tools

Standard Tools (from the wheel)

Standard DPYC(TM) tools are registered by register_standard_tools() from tollbooth-dpyc. These include session management, credit operations, Secure Courier, pricing, notarization, and Oracle delegation. Each tool is identified by a deterministic UUID v5.

Category	Tools
Session & Billing	`session_status`, `check_balance`, `account_statement`, `account_statement_infographic`, `restore_credits`, `service_status`, `check_price`, `check_authority_balance`
Secure Courier	`request_credential_channel`, `receive_credentials`, `forget_credentials`
Npub Proof	`request_npub_proof`, `receive_npub_proof`
Purchase	`purchase_credits`, `check_payment`
Pricing & Constraints	`get_pricing_model`, `set_pricing_model`, `reset_pricing_model`, `list_constraint_types`
Notarization	`notarize_ledger`, `list_notarizations`, `get_notarization_proof`
Onboarding	`get_operator_onboarding_status`, `get_patron_onboarding_status`
Oracle (delegated)	`oracle_about`, `oracle_how_to_join`, `oracle_lookup_member`, `oracle_get_tax_rate`, `oracle_network_advisory`

Domain Tools (eXcalibur-specific)

Tool	Cost	Description
`begin_oauth`	Free	Start X OAuth2 Authorization Code + PKCE flow; returns `authorize_url`
`check_oauth_status`	Free	Complete the browser authorization and exchange the code for tokens
`post_tweet`	ad valorem	Post to X with markdown-to-Unicode rich text formatting
`post_tweet_image`	ad valorem	Post with an image URL or SVG banner (rendered to PNG)

All tools that take an npub also accept a proof: str parameter for kind-27235 Schnorr proof attestation.

Security

Npub identity -- Patrons are identified by a Nostr public key (npub), not an email or password. One keypair per role, managed by the user.
Kind-27235 Schnorr proof -- Tool calls carry an NIP-98-style Schnorr signature proving the caller controls the claimed npub. Proof is cached for ~1 hour; renew via request_npub_proof / receive_npub_proof.
Human-in-the-loop Secure Courier -- Credential delivery requires conscious operator approval via Nostr DM. On receipt, the relay message is destructively drained so secrets exist only in the encrypted Neon vault.
Per-operator Neon schema -- Each operator's credentials are stored in an isolated Postgres schema with a dedicated LOGIN role. No cross-operator access.

Architecture

code

src/excalibur_mcp/
  server.py        FastMCP server -- domain tools + register_standard_tools()
  config.py        Pydantic settings from environment variables
  oauth_flow.py    X-specific OAuth2 Authorization Code + PKCE wrapper
  vault.py         In-memory Bearer token session cache (keyed by npub)
  x_client.py      X API v2 client with OAuth 2.0 Bearer token auth
  formatter.py     Markdown -> Unicode rich text (bold, italic, headers)

Key design choices:

OAuth2 Authorization Code + PKCE -- Patron tokens acquired via browser flow. begin_oauth returns the primary authorize_url (not a shortlink); check_oauth_status completes the exchange. Tokens stored in Neon vault, auto-refreshed on expiry. No OAuth 1.0a.
UUID v5 tool identity -- Every tool (standard and domain) has a deterministic UUID derived from its capability name. Pricing, constraints, and billing all key on UUID.
Standard tools from the wheel -- register_standard_tools() provides all DPYC(TM) infrastructure tools. Only domain-specific X/Twitter tools are defined in server.py.
Markdown to Unicode -- Converts **bold**, *italic*, and # headers to Unicode characters that render in tweets without markup syntax.

Self-Hosting

Environment Variables

DPYC(TM) Identity (required to boot)

Variable	Required	Description
`TOLLBOOTH_NOSTR_OPERATOR_NSEC`	Yes	Operator's Nostr secret key for identity bootstrap and DM encryption

This is the only env var required to start. All other secrets (X app keys, BTCPay credentials) arrive via Secure Courier credential templates and are stored in the per-operator Neon vault schema.

Operator Credentials (via Secure Courier)

These are delivered via Secure Courier (service="excalibur-operator"), not set as environment variables:

Credential	Description
`client_id`	X OAuth2 Client ID (from X Developer Portal)
`client_secret`	X OAuth2 Client Secret (from X Developer Portal)
`btcpay_host`	BTCPay Server URL
`btcpay_store_id`	Store ID for invoices
`btcpay_api_key`	API key with invoice permissions

Certified operators bootstrap their Neon database URL from the Authority via encrypted Nostr DM -- NEON_DATABASE_URL is not read from the environment.

Optional Tuning

Variable	Description
`TOLLBOOTH_NOSTR_RELAYS`	Comma-separated relay URLs (overrides defaults)
`SEED_BALANCE_SATS`	Starter credits for new users (default: 0)
`DPYC_REGISTRY_CACHE_TTL_SECONDS`	How long to cache the DPYC community registry (default: 300)
`CONSTRAINTS_ENABLED`	`"true"` to enable constraint engine evaluation on tool calls

Troubleshooting

Cold start

On first request after deploy, the service may take a few seconds to initialize Neon connections and load the pricing model. The runtime handles this with inline retry -- the caller receives the result after the warm-up completes, not a "service unavailable" error.

Credential lifecycle states

Credential-related responses describe the current lifecycle state with clear guidance, not error messages:

State	Meaning	Next step
`no_session`	No npub recognized	Call `session_status` with your npub
`awaiting_oauth`	OAuth flow started, browser not yet authorized	Open the `authorize_url` and authorize
`awaiting_courier`	Secure Courier channel opened, credentials not yet received	Reply via Nostr client with credentials JSON
`proof_expired`	Npub proof cache expired (~1 hour)	Call `request_npub_proof` then `receive_npub_proof`
`insufficient_balance`	Credits exhausted or tranche expired	Call `purchase_credits` to top up

Common tool call situations

"proof is required" -- Call request_npub_proof then receive_npub_proof to prove npub ownership. The cache expires after ~1 hour; renew with a fresh request/receive cycle.
"Insufficient credit balance" -- Call purchase_credits to top up. Check tranche expiry with check_balance.
"Operator credentials not configured" -- Operator setup issue, not the patron's problem.

Don't Pester Your Customer: Do NOT ask the patron to re-authenticate, re-authorize, or re-do OAuth unless the response specifically says the upstream token is expired or invalid.

Development

bash

# Install in development mode
cd excalibur-mcp
python -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]"

# Run tests
.venv/bin/pytest tests/

# Type checking
mypy src/excalibur_mcp/

# Formatting
black src/ tests/
ruff check src/ tests/

DPYC(TM) Ecosystem

tollbooth-dpyc -- Python SDK for Tollbooth monetization (vault, auth, pricing, Lightning payments, Nostr identity)
dpyc-community -- Governance registry: membership, advisories, threat model
dpyc-oracle -- Community concierge (free onboarding + member lookup)
tollbooth-authority -- Certification backbone (Schnorr-signed purchase-order certificates)
tollbooth-sample -- Sample Operator (canonical template)
tollbooth-pricing-studio -- iOS pricing-model editor / operator console
cypher-mcp -- Monetized graph answers: named Cypher templates over Neo4j/AuraDB
schwab-mcp -- Charles Schwab brokerage data
thebrain-mcp -- TheBrain personal knowledge graph
excalibur-mcp -- X/Twitter posting
taxsort-mcp -- Tax classification + Cloudflare Pages UI
optionality-mcp -- Options analytics (brokerage-data operator)
tollbooth-oauth2-collector -- OAuth2 callback handler (advocate service)
tollbooth-shortlinks -- URL shortener utility

Trademarks

DPYC, Tollbooth DPYC, and Don't Pester Your Customer are trademarks of Lonnie VanZandt. See the TRADEMARKS.md in the dpyc-community repository for usage guidelines.

License

Apache License 2.0 -- see LICENSE for details.

Install

Tools (67)

excalibur_check_balanceexcalibur_purchase_creditsexcalibur_check_paymentexcalibur_restore_creditsexcalibur_account_statementexcalibur_account_statement_infographicexcalibur_service_statusexcalibur_get_operator_onboarding_status

Remote endpoint

Streamable HTTP

Hosted server - connect over the network, no local install.

url

https://excalibur-mcp.fastmcp.app/mcp

Add to VS Code Add to Cursor

claude_desktop_config.json

json

{
  "mcpServers": {
    "excalibur-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://excalibur-mcp.fastmcp.app/mcp"
      ]
    }
  }
}

Desktop config is stdio-only; this bridges via mcp-remote. Native remote: Settings > Connectors.