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io.github.lonniev/excalibur-mcp

REMOTE · EXCALIBUR-MCP.FASTMCP.APP · SCANNED SEP 21

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

0 this week 74 Trust /100
Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →

Endpoint Security57
Transport & Reachability100
Schema Quality & AI Usability62
  • AI-judged instruction clarity (good).Pass
  • Context-footprint check failed: tool/resource definitions use about 14114 tokens (~178/item across 79 items; 79 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
  • No destabilizing schema changes in the last 30 days.Pass
Tool Coverage88
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 58% of tool parameters carry a description.Partial
  • Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety75
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • 0 of 11 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "excalibur_forget_credentials" implies "delete" and declares no destructiveHint at all, which the MCP spec reads as destructive by default. See how to fix → Fail
  • An AI judge read all 80 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Install

How do I install the io.github.lonniev/excalibur-mcp server?

io.github.lonniev/excalibur-mcp is a hosted endpoint at https://excalibur-mcp.fastmcp.app/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

remote · excalibur-mcp.fastmcp.app

# add to Claude Code
claude mcp add --transport http lonniev-excalibur-mcp 'https://excalibur-mcp.fastmcp.app/mcp'
// .cursor/mcp.json
{
  "mcpServers": {
    "lonniev-excalibur-mcp": {
      "url": "https://excalibur-mcp.fastmcp.app/mcp"
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "lonniev-excalibur-mcp": {
      "type": "http",
      "url": "https://excalibur-mcp.fastmcp.app/mcp"
    }
  }
}
# ~/.codex/config.toml
[mcp_servers.lonniev-excalibur-mcp]
url = "https://excalibur-mcp.fastmcp.app/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "lonniev-excalibur-mcp": {
      "type": "remote",
      "url": "https://excalibur-mcp.fastmcp.app/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add lonniev-excalibur-mcp --url 'https://excalibur-mcp.fastmcp.app/mcp' --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  lonniev-excalibur-mcp:
    url: "https://excalibur-mcp.fastmcp.app/mcp"
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "lonniev-excalibur-mcp": {
      "Transport": "http",
      "Url": "https://excalibur-mcp.fastmcp.app/mcp"
    }
  }
}
# add to Vellum
assistant mcp add lonniev-excalibur-mcp -t streamable-http -u 'https://excalibur-mcp.fastmcp.app/mcp'
// mcp.json
{
  "mcpServers": {
    "lonniev-excalibur-mcp": {
      "type": "http",
      "url": "https://excalibur-mcp.fastmcp.app/mcp"
    }
  }
}

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 16 Sept 26 0
    • New tool “excalibur_scheduler_reissue” functional
  • 26 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 25 Aug 26 0
    • Stability: 0.97 → pass security
  • 24 Aug 26 +1
    • Tool “excalibur_scheduler_check_now” rewrote its description, which is the text the model reads security
    • “excalibur_scheduler_check_now” reworded the description of “npub” cosmetic
  • 21 Aug 26 0
    • Tool “excalibur_list_posts” rewrote its description, which is the text the model reads security
    • “excalibur_list_posts” added an optional parameter “sent_hour” cosmetic
    • “excalibur_list_posts” added an optional parameter “time_zone” cosmetic
  • 17 Aug 26 0
    • Tool “excalibur_account_statement” rewrote its description, which is the text the model reads security
    • Tool “excalibur_account_statement_infographic” rewrote its description, which is the text the model reads security
    • Tool “excalibur_begin_oauth” rewrote its description, which is the text the model reads security
    • Tool “excalibur_check_balance” rewrote its description, which is the text the model reads security
    • Tool “excalibur_check_oauth_status” rewrote its description, which is the text the model reads security
    • Tool “excalibur_check_payment” rewrote its description, which is the text the model reads security
    • Tool “excalibur_check_price” rewrote its description, which is the text the model reads security
    • Tool “excalibur_check_proof_status” rewrote its description, which is the text the model reads security
    • Tool “excalibur_create_post” rewrote its description, which is the text the model reads security
    • Tool “excalibur_delete_patron_credential” rewrote its description, which is the text the model reads security
    • Tool “excalibur_forget_credentials” rewrote its description, which is the text the model reads security
    • Tool “excalibur_get_notarization_proof” rewrote its description, which is the text the model reads security
    • Tool “excalibur_get_patron_credential_fields” rewrote its description, which is the text the model reads security
    • Tool “excalibur_get_patron_onboarding_status” rewrote its description, which is the text the model reads security
    • Tool “excalibur_list_notarizations” rewrote its description, which is the text the model reads security
    • Tool “excalibur_mint_coupon” rewrote its description, which is the text the model reads security
    • Tool “excalibur_post_nostr_message” rewrote its description, which is the text the model reads security
    • Tool “excalibur_post_tweet” rewrote its description, which is the text the model reads security
    • Tool “excalibur_post_tweet_image” rewrote its description, which is the text the model reads security
    • Tool “excalibur_publish_nostr_profile” rewrote its description, which is the text the model reads security
    • Tool “excalibur_purchase_credits” rewrote its description, which is the text the model reads security
    • Tool “excalibur_receive_credentials” rewrote its description, which is the text the model reads security
    • Tool “excalibur_receive_npub_proof” rewrote its description, which is the text the model reads security
    • Tool “excalibur_refine_post_region” rewrote its description, which is the text the model reads security
    • Tool “excalibur_report_issue” rewrote its description, which is the text the model reads security
    • Tool “excalibur_request_adoption” rewrote its description, which is the text the model reads security
    • Tool “excalibur_request_credential_channel” rewrote its description, which is the text the model reads security
    • Tool “excalibur_request_npub_proof” rewrote its description, which is the text the model reads security
    • Tool “excalibur_resolve_dynamic_block” rewrote its description, which is the text the model reads security
    • Tool “excalibur_restore_credits” rewrote its description, which is the text the model reads security
    • Tool “excalibur_session_status” rewrote its description, which is the text the model reads security
    • Tool “excalibur_update_operator_credential” rewrote its description, which is the text the model reads security
    • Tool “excalibur_update_patron_credential” rewrote its description, which is the text the model reads security
    • Tool coverage: 14% → 58% functional
    • The server now declares the “logging” capability functional
    • Server version: 3.0.2 → 3.4.7 functional
    • New tool “excalibur_delete_operator_credential” functional
    • “excalibur_account_statement” reworded the description of “days” cosmetic
    • “excalibur_account_statement” reworded the description of “dpop_token” cosmetic
    • “excalibur_account_statement” reworded the description of “npub” cosmetic
    • “excalibur_account_statement_infographic” reworded the description of “days” cosmetic
    • “excalibur_account_statement_infographic” reworded the description of “dpop_token” cosmetic
    • “excalibur_account_statement_infographic” reworded the description of “npub” cosmetic
    • “excalibur_begin_oauth” reworded the description of “dpop_token” cosmetic
    • “excalibur_begin_oauth” reworded the description of “npub” cosmetic
    • “excalibur_check_balance” reworded the description of “dpop_token” cosmetic
    • “excalibur_check_balance” reworded the description of “npub” cosmetic
    • “excalibur_check_oauth_status” reworded the description of “dpop_token” cosmetic
    • “excalibur_check_oauth_status” reworded the description of “npub” cosmetic
    • “excalibur_check_payment” reworded the description of “dpop_token” cosmetic
    • “excalibur_check_payment” reworded the description of “invoice_id” cosmetic
    • “excalibur_check_payment” reworded the description of “npub” cosmetic
    • “excalibur_check_price” reworded the description of “tool_id” cosmetic
    • “excalibur_check_price” reworded the description of “tool_kwargs” cosmetic
    • “excalibur_check_proof_status” reworded the description of “dpop_token” cosmetic
    • “excalibur_check_proof_status” reworded the description of “patron_npub” cosmetic
    • “excalibur_create_post” reworded the description of “cease_at” cosmetic
    • “excalibur_create_post” reworded the description of “client_req_id” cosmetic
    • “excalibur_create_post” reworded the description of “doc” cosmetic
    • “excalibur_create_post” reworded the description of “publish_at” cosmetic
    • “excalibur_create_post” reworded the description of “recurrence” cosmetic
    • “excalibur_create_post” reworded the description of “status” cosmetic
    • “excalibur_create_post” reworded the description of “text_cache” cosmetic
    • “excalibur_create_post” reworded the description of “title” cosmetic
    • “excalibur_delete_patron_credential” reworded the description of “dpop_token” cosmetic
    • “excalibur_delete_patron_credential” reworded the description of “field” cosmetic
    • “excalibur_delete_patron_credential” reworded the description of “npub” cosmetic
    • “excalibur_forget_credentials” reworded the description of “dpop_token” cosmetic
    • “excalibur_forget_credentials” reworded the description of “npub” cosmetic
    • “excalibur_forget_credentials” reworded the description of “service” cosmetic
    • “excalibur_get_notarization_proof” reworded the description of “notarization_id” cosmetic
    • “excalibur_get_notarization_proof” reworded the description of “npub” cosmetic
    • “excalibur_get_patron_credential_fields” reworded the description of “dpop_token” cosmetic
    • “excalibur_get_patron_credential_fields” reworded the description of “npub” cosmetic
    • “excalibur_get_patron_onboarding_status” reworded the description of “dpop_token” cosmetic
    • “excalibur_get_patron_onboarding_status” reworded the description of “patron_npub” cosmetic
    • “excalibur_list_notarizations” reworded the description of “limit” cosmetic
    • “excalibur_list_notarizations” reworded the description of “status” cosmetic
    • “excalibur_mint_coupon” reworded the description of “discount_percent” cosmetic
    • “excalibur_mint_coupon” reworded the description of “name” cosmetic
    • “excalibur_mint_coupon” reworded the description of “total_uses” cosmetic
    • “excalibur_mint_coupon” reworded the description of “uses_per_patron” cosmetic
    • “excalibur_mint_coupon” reworded the description of “valid_from” cosmetic
    • “excalibur_mint_coupon” reworded the description of “valid_until” cosmetic
    • “excalibur_post_nostr_message” reworded the description of “message” cosmetic
    • “excalibur_post_tweet” reworded the description of “text” cosmetic
    • “excalibur_post_tweet_image” reworded the description of “banner_svg” cosmetic
    • “excalibur_post_tweet_image” reworded the description of “image_url” cosmetic
    • “excalibur_post_tweet_image” reworded the description of “text” cosmetic
    • “excalibur_publish_nostr_profile” reworded the description of “npub” cosmetic
    • “excalibur_publish_nostr_profile” reworded the description of “signed_event” cosmetic
    • “excalibur_purchase_credits” reworded the description of “amount_sats” cosmetic
    • “excalibur_purchase_credits” reworded the description of “dpop_token” cosmetic
    • “excalibur_purchase_credits” reworded the description of “npub” cosmetic
    • “excalibur_receive_credentials” reworded the description of “credential_card” cosmetic
    • “excalibur_receive_credentials” reworded the description of “dpop_token” cosmetic
    • “excalibur_receive_credentials” reworded the description of “sender_npub” cosmetic
    • “excalibur_receive_credentials” reworded the description of “service” cosmetic
    • “excalibur_receive_npub_proof” reworded the description of “dpop_token” cosmetic
    • “excalibur_receive_npub_proof” reworded the description of “patron_npub” cosmetic
    • “excalibur_refine_post_region” reworded the description of “bans” cosmetic
    • “excalibur_refine_post_region” reworded the description of “full_text” cosmetic
    • “excalibur_refine_post_region” reworded the description of “instruction” cosmetic
    • “excalibur_refine_post_region” reworded the description of “region” cosmetic
    • “excalibur_refine_post_region” reworded the description of “voice” cosmetic
    • “excalibur_report_issue” reworded the description of “body” cosmetic
    • “excalibur_report_issue” reworded the description of “dpop_token” cosmetic
    • “excalibur_report_issue” reworded the description of “npub” cosmetic
    • “excalibur_report_issue” reworded the description of “title” cosmetic
    • “excalibur_report_issue” reworded the description of “tool_name” cosmetic
    • “excalibur_request_adoption” reworded the description of “authority_npub” cosmetic
    • “excalibur_request_adoption” reworded the description of “dpop_token” cosmetic
    • “excalibur_request_adoption” reworded the description of “note” cosmetic
    • “excalibur_request_adoption” reworded the description of “service_url” cosmetic
    • “excalibur_request_credential_channel” reworded the description of “sender_npub” cosmetic
    • “excalibur_request_credential_channel” reworded the description of “service” cosmetic
    • “excalibur_request_npub_proof” reworded the description of “patron_npub” cosmetic
    • “excalibur_request_npub_proof” reworded the description of “reason” cosmetic
    • “excalibur_request_npub_proof” reworded the description of “verify_at” cosmetic
    • “excalibur_resolve_dynamic_block” reworded the description of “allowed_domains” cosmetic
    • “excalibur_resolve_dynamic_block” reworded the description of “bans” cosmetic
    • “excalibur_resolve_dynamic_block” reworded the description of “context” cosmetic
    • “excalibur_resolve_dynamic_block” reworded the description of “max_fetches” cosmetic
    • “excalibur_resolve_dynamic_block” reworded the description of “prompt” cosmetic
    • “excalibur_resolve_dynamic_block” reworded the description of “voice” cosmetic
    • “excalibur_restore_credits” reworded the description of “dpop_token” cosmetic
    • “excalibur_restore_credits” reworded the description of “invoice_id” cosmetic
    • “excalibur_restore_credits” reworded the description of “patron_npub” cosmetic
    • “excalibur_session_status” reworded the description of “patron_npub” cosmetic
    • “excalibur_update_operator_credential” reworded the description of “dpop_token” cosmetic
    • “excalibur_update_operator_credential” reworded the description of “field” cosmetic
    • “excalibur_update_operator_credential” reworded the description of “value” cosmetic
    • “excalibur_update_patron_credential” reworded the description of “dpop_token” cosmetic
    • “excalibur_update_patron_credential” reworded the description of “field” cosmetic
    • “excalibur_update_patron_credential” reworded the description of “npub” cosmetic
    • “excalibur_update_patron_credential” reworded the description of “value” cosmetic
  • 11 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 10 Aug 26 0
    • Tool “excalibur_list_posts” rewrote its description, which is the text the model reads security
    • Tool “excalibur_list_snippets” rewrote its description, which is the text the model reads security
Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 21 Sept 2026 · Probed https://excalibur-mcp.fastmcp.app/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=*.fastmcp.app CN=Amazon RSA 2048 M04,O=Amazon,C=US 17 Jun 2026 31 Dec 2026 RSA 2048 SHA256-RSA a1583bafd89c7b58780ef1a0a0d2ad7
SANs: *.fastmcp.app
CN=Amazon RSA 2048 M04,O=Amazon,C=US (CA) CN=Amazon Root CA 1,O=Amazon,C=US 23 Aug 2022 23 Aug 2030 RSA 2048 SHA256-RSA 773124f2a952e3ed18a58bdb85d1bc0ce5f27
CN=Amazon Root CA 1,O=Amazon,C=US (CA) CN=Starfield Services Root Certificate Authority - G2,O=Starfield Technologies\, Inc.,L=Scottsdale,ST=Arizona,C=US 25 May 2015 31 Dec 2037 RSA 2048 SHA256-RSA 67f944a2a27cdf3fac2ae2b01f908eeb9c4c6

Background: What to check on a remote MCP endpoint →

DNSSEC insecure

Validation of excalibur-mcp.fastmcp.app. Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
app. present 23684 8 Verified
fastmcp.app. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 200

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://excalibur-mcp.fastmcp.app/mcp Verified 200
http (plaintext) http://excalibur-mcp.fastmcp.app/mcp HTTPS enforced 301 https://excalibur-mcp.fastmcp.app/mcp
MCP tools · 79 exposed · ~13,432 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
excalibur_post_tweet_image ~140

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.

NameTypeReqDescription
banner_svgstringSelf-contained SVG markup string, converted to PNG.
dpop_tokenstring
image_urlstringURL of an image to attach to the tweet.
npubstringRequired. Your Nostr public key (npub1...) for credit billing.
textstringyesTweet content with optional markdown formatting.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_process_scheduled_posts ~206

Launch a publisher for every due post (operator-only). Selects ``scheduled`` posts whose ``publish_at`` has arrived, claims each atomically, and starts one background publisher per post. It does NOT publish: composing content, billing the owner, posting to X and recording the outcome all belong to the publisher, which runs on the async job queue and so may take the minutes a dynamic block needs. This call returns as soon as the work is dispatched — expect it to be fast even when the publishing itself is slow, and read per-post outcomes from ``get_scheduler_log`` or the post rows. Requires the operator's npub proof; the trigger itself is free. Returns ``{kind: "tick", processed, launched, contended}``.

NameTypeReqDescription
dpop_tokenstring
npubstringThe OPERATOR's npub (npub1...); this tool is operator-only.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_publish_nostr_profile ~151

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.

NameTypeReqDescription
npubstringThe patron's Nostr public key the event must be signed by.
signed_eventstringA JSON-encoded, client-signed kind-0 event.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_purchase_credits ~200

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.

NameTypeReqDescription
amount_satsintegerSatoshis to purchase (default 1000).
dpop_tokenstringyesRaw JSON of a kind-27235 Nostr event signed by npub — not base64, not NIP-98 'Authorization: Nostr <b64>' framing. Its `u` tag must hold THIS tool's exact name (from tools/list), not the endpoint URL…
npubstringyesThe Nostr public key (npub1...) the credits will fund.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_receive_credentials ~324

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.

NameTypeReqDescription
credential_cardstringOptional. An ncred1... card to redeem directly (bypasses the relay drain; dpop_token not needed).
dpop_tokenstringRequired. The session phrase returned by request_credential_channel for this exact channel.
sender_npubstringRequired. The npub that sent the credentials.
servicestringRequired. The credential service name (must match the service used in request_credential_channel).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_receive_npub_proof ~311

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.

NameTypeReqDescription
dpop_tokenstringRequired. The dpop_token returned by request_npub_proof.
patron_npubstringRequired. The patron's npub to receive proof from.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_redeem_coupon ~135

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.

NameTypeReqDescription
codestringyes
dpop_tokenstring
npubstringyes

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_refine_post_region ~252

Refine a flagged region of a post with an LLM — server-side. The operator's LLM 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 LLM key is configured or the upstream call returns nothing.

NameTypeReqDescription
bansstringBanned constructions — JSON array or comma-separated (optional).
dpop_tokenstring
full_textstringThe whole tweet, for context.
instructionstringWhat the editor wants changed (optional).
npubstringRequired. Your Nostr public key (npub1...) for credit billing.
regionstringyesThe flagged span to rewrite.
voicestringVoice-profile text fed to the model (optional).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_report_issue ~349

File a field report about this service as a GitHub issue on the operator's repo. Found a tool's metadata or response wrong or confusing? Report it where the tool lives. The **author of record is your npub** — no npub / no proof, no issue — and it is stamped into the issue so the report is attributed to you, not the operator. Costs a small fee (a free write to an issue tracker would be abused). The report is PUBLIC and goes to the maintainers' normal triage; nothing is verified here. Returns the filed issue's repo, number, and url. If this operator has not enabled field reports, returns an "issue reporting not configured" situation and you are not charged.

NameTypeReqDescription
bodystringyesThe details — which tool, what was wrong, what you expected.
dpop_tokenstringyesRaw JSON of a kind-27235 Nostr event signed by npub — not base64, not NIP-98 'Authorization: Nostr <b64>' framing. Its `u` tag must hold THIS tool's exact name (from tools/list), not the endpoint URL…
npubstringyesYour Nostr public key (npub1...); the report's author of record.
titlestringyesOne-line summary of the problem.
tool_namestringOptional: the specific tool the report is about (e.g. "schwab_get_option_chain").

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_request_adoption ~194

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.

NameTypeReqDescription
authority_npubstringyesnpub of the Authority to request adoption from.
dpop_tokenstringoperator-npub ownership proof (inline kind-27235 or cached token).
notestringoptional message for the Authority owner.
service_urlstringthis operator's MCP endpoint (advertised to the Authority).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_request_credential_channel ~252

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.

NameTypeReqDescription
sender_npubstringRequired. The npub to send the template to.
servicestringRequired. The credential service name (e.g., from get_operator_onboarding_status or get_patron_onboarding_status).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_request_npub_proof ~489

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.

NameTypeReqDescription
patron_npubstringRequired. The patron's npub to request proof from.
reasonstringOptional. A human-readable purpose for the request ("I'm working on your request XYZ and need the Operator to do ABC for you"). Signed into the provenance attestation and shown in the DM, so the reci…
verify_atstringOptional. A free-form statement of WHERE you (the initiating agent) already showed this proof's one-time code to the user — a URL, or "your Claude.ai conversation", "the Grok session". The OAuth 2.0…

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_reset_pricing_model ~82

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).

NameTypeReqDescription
dpop_tokenstring

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_resolve_dynamic_block ~453

Start resolving a dynamic post block with an LLM — returns a CLAIM CHECK. A dynamic block's ``prompt`` is run by the model (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 LLM 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 LLM key is configured or the job ultimately fails.

NameTypeReqDescription
allowed_domainsstringAuthor allowlist for web_fetch — JSON array or comma-separated. Blank = fetch any URL the prompt references.
bansstringBanned constructions — JSON array or comma-separated (optional).
contextstringThe surrounding composed post (may contain the ⟨HERE⟩ marker).
dpop_tokenstring
max_fetchesintegerAuthor budget for web lookups (search + fetch), 1..25.
npubstringRequired. Your Nostr public key (npub1...) for credit billing.
promptstringyesThe dynamic block's prompt to run.
runtime_limit_secondsintegerAuthor's time budget for this block in seconds (60–1800). Bounds how long the job may run AND sets the poll cadence; the operator may price it ad valorem.
voicestringVoice-profile text fed to the model (optional).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_restore_credits ~235

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.

NameTypeReqDescription
dpop_tokenstringyesA kind-27235 Nostr event signed by the OPERATOR's nsec for this tool. Patron proofs are rejected.
invoice_idstringyesThe BTCPay invoice ID to verify and credit.
patron_npubstringyesThe patron's npub whose ledger receives the grant.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_restore_neon_schema ~149

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).

NameTypeReqDescription
dpop_tokenstring

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_save_snippet ~202

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": …}``.

NameTypeReqDescription
doc
dpop_tokenstring
favorite
namestring
npubstringRequired. Your Nostr public key (npub1...).
snippet_idstring
textstring

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_save_voice ~158

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": {...}}``.

NameTypeReqDescription
bans
dpop_tokenstring
npubstringRequired. Your Nostr public key (npub1...).
profilestring

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_scheduler_check_now ~242

Ask the scheduler to run one tick now (free; any proven patron). Pokes the Worker's ``/tick`` — the same work the ~30-minute cron does: it claims a pending proof reply (completing the operator's authorization) and fires any due posts. Use it right after the operator approves in Studio so nobody waits for the next tick. Deliberately NOT operator-only. Approving is the operator's act; noticing that they approved is anyone's, and a patron watching a parked scheduler is often the one who notices first. The poke carries no authority — it cannot approve anything, only ask the Worker to look. The challenge phrase stays operator-gated (``scheduler_pending``). The Worker runs the tick in the background and returns immediately; re-read ``scheduler_status`` a few seconds later to see the phase flip. Returns ``{started: true}`` or ``{started: false}`` if the Worker couldn't be reached.

NameTypeReqDescription
dpop_tokenstring
npubstringYour npub (npub1...).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_scheduler_pending ~224

What is the scheduled-post cron Worker waiting on? (operator-only). When the Worker's authorization lapses it DMs the operator a challenge phrase and parks. This returns that pending phrase so the operator can match it against the DM before approving in Studio — the Device-Grant second surface for a headless actor. The phrase lives only in the Worker's KV (an impostor can't inject it); we read it AS the operator (a kind-27235 signed with the operator key), so the human never signs anything in the browser. ``restricted``: gated to the operator npub, free. Never returns the active session token. Returns ``{phase, code, reason, requestedAt}`` — ``phase`` is ``pending`` / ``active`` / ``idle``, or ``unavailable`` if the Worker can't be reached.

NameTypeReqDescription
dpop_tokenstring
npubstringThe OPERATOR's npub (npub1...); this tool is operator-only.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_scheduler_reissue ~202

Send the scheduler's proof request again, now (operator-only). For a pending request that is not going to complete — the reply went to an older DM, or ``scheduler_pending`` shows a last check that says the request was replaced or expired. The Worker drops it and DMs a fresh one straight away instead of waiting out its hour. Approve the NEWEST DM in Studio, then ``scheduler_check_now``. Signed as the operator with a sentinel ``u``-tag the Worker checks literally, like ``scheduler_pending``, so the browser signs nothing. An already-authorized scheduler is left alone. ``restricted``: gated to the operator npub, free. Returns ``{success, phase, requestedAt, message}``.

NameTypeReqDescription
dpop_tokenstring
npubstringThe OPERATOR's npub (npub1...); this tool is operator-only.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_scheduler_status ~158

The scheduler's configuration and current status (free; any proven patron). Relays the cron Worker's public ``/status`` — cadence, version, renewal window, and current authorization phase (``pending`` / ``active`` / ``idle``, no challenge phrase) — and adds the operator npub it acts for. No secrets: the pending phrase (operator-only) is ``scheduler_pending``; the per-tick traffic log is ``get_scheduler_log``. Returns the merged config, or ``{worker: "unavailable"}`` merged in if the Worker can't be reached.

NameTypeReqDescription
dpop_tokenstring
npubstringYour npub (npub1...).

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_service_status ~22

Check the health and configuration of this service. Free.

Input schema present but exposes no named parameters.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_session_status ~287

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. - quota_exceeded: The persistence provider (Neon) answered HTTP 402 — the operator's database has exhausted its compute/storage quota, so the books are locked for billing. Paid tools fail; retrying does NOT help. The operator's Authority must restore capacity (upgrade the plan or wait for the quota reset). Free tools remain available. - not_registered: Operator has no Authority relationship yet. Call register_operator first. - no_identity: Operator nsec is not configured. Deployment issue.

NameTypeReqDescription
patron_npubstringOptional. 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…

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_set_pricing_model ~69

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.

NameTypeReqDescription
dpop_tokenstring
model_jsonstringyes

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_update_coupon ~168

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.

NameTypeReqDescription
clear_total_usesboolean
clear_uses_per_patronboolean
coupon_idstringyes
discount_percent
dpop_tokenstring
name
total_uses
uses_per_patron
valid_from
valid_until

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_update_operator_credential ~183

Add or update a single operator secret field. Merges into the operator's stored credentials without touching the others — the field-level counterpart to re-delivering the whole bundle over Secure Courier. Use it to rotate one secret (a reissued ``btcpay_api_key``, say) without restating the six you did not change, where any field omitted from a courier reply is destroyed. The value is never echoed back. RESTRICTED to the operator — requires proof (nsec-signed kind-27235 or a cached dpop_token phrase); patron proofs are rejected.

NameTypeReqDescription
dpop_tokenstringyesOperator proof for this tool.
fieldstringyesThe operator credential field to set. Must be declared in the operator's credential template.
valuestringyesThe value to store.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_update_patron_credential ~219

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.

NameTypeReqDescription
dpop_tokenstringyesRaw JSON of a kind-27235 Nostr event signed by npub — not base64, not NIP-98 'Authorization: Nostr <b64>' framing. Its `u` tag must hold THIS tool's exact name (from tools/list), not the endpoint URL…
fieldstringyesThe credential field name to set.
npubstringyesThe patron's Nostr public key (npub1...).
valuestringyesThe value to store.

Structured output declared, but exposes no named fields.

No examples provided.

excalibur_update_post ~150

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.

NameTypeReqDescription
client_req_idstring
dpop_tokenstring
npubstringRequired. Your Nostr public key (npub1...) for credit billing.
patchobjectyes
post_idstringyes
text_cachestring

Structured output declared, but exposes no named fields.

No examples provided.

Common questions

What is the io.github.lonniev/excalibur-mcp server?

io.github.lonniev/excalibur-mcp is listed in the public MCP registry as io.github.lonniev/excalibur-mcp. FastMCP server for posting formatted content to X (Twitter), Tollbooth-monetized, DPYC-native. This page covers its hosted endpoint (https://excalibur-mcp.fastmcp.app/mcp).

Is the io.github.lonniev/excalibur-mcp server safe to use?

io.github.lonniev/excalibur-mcp scores 74 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the io.github.lonniev/excalibur-mcp server expose?

io.github.lonniev/excalibur-mcp exposes 79 tools: excalibur_check_balance, excalibur_purchase_credits, excalibur_check_payment, excalibur_restore_credits, excalibur_account_statement, and 74 more. Their descriptions and schemas cost roughly 13,432 tokens of context every time the server is loaded.

Does the io.github.lonniev/excalibur-mcp server require authentication?

No. We connected to io.github.lonniev/excalibur-mcp without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

Is the io.github.lonniev/excalibur-mcp server still maintained?

io.github.lonniev/excalibur-mcp is still listed as active in the MCP registry. We last reached this channel on 21 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.