Excalibur MCP - install, status & alternatives [2026]

01 · Install Excalibur MCP

Claude Code

claude mcp add lonniev-excalibur-mcp --transport http https://excalibur-mcp.fastmcp.app/mcp

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "lonniev-excalibur-mcp": {
      "url": "https://excalibur-mcp.fastmcp.app/mcp"
    }
  }
}

Same JSON for Cursor. For VS Code, rename the top-level key from `mcpServers` to `servers`.

Using another client? Same JSON, different key

Claude Desktop · mcpServers

Cursor · mcpServers

VS Code · servers

Windsurf · mcpServers

Zed · context_servers

Cline · mcpServers

Roo Code · mcpServers

Continue · mcpServers

LibreChat · mcpServers

Gemini CLI · mcpServers

Codex CLI · mcp_servers

Full setup guides: every client.

02 · Evidence

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

transport: streamable-http

endpoint alive - responded to MCP initialize · probed 2026-09-17

Security posture

What to check before giving this server access to your agent - from the registry, GitHub, and our own probes. We don't score safety; we show what's verifiable.

runs as remote - your agent's requests go to excalibur-mcp.fastmcp.app

endpoint auth accepted our unauthenticated MCP initialize - no credentials needed to connect

license no standard license detected - usage rights unclear; check the repo before commercial use

registry namespace io.github.lonniev is GitHub-verified and matches the repo owner

03 · What Excalibur MCP can do

Prose above is summarized from the project's README and registry record - no invented capabilities.

What you can build

With this server connected, an agent can post a text tweet with markdown-to-Unicode rich text formatting, post a tweet with a hero banner image (image URL or SVG rendered to PNG), fetch the connected X account's handle and name for this patron (free), and read one stored post by id (owner-scoped).

Capability map

Tools grouped from the project's README - what Excalibur MCP lets an agent do.

read & search

6 tools - e.g. Fetch the connected X account's handle and name for this patron (free); Read one stored post by id (owner-scoped); List your stored posts, server-side sorted, filtered, and paginated

get_x_profile · get_post · list_posts · list_snippets · get_voice · fetch_dynamic_block

Scheduler

5 tools - e.g. Read recent scheduler-tick outcomes; The scheduler's configuration and current status (free; any proven patron); What the scheduled-post cron Worker is waiting on (operator-only)

get_scheduler_log · scheduler_status · scheduler_pending · scheduler_check_now · scheduler_reissue

Snippet

3 tools - e.g. Read one saved snippet by id; Save a reusable snippet (opening/footer/CTA); Delete a saved snippet (free, owner-scoped)

get_snippet · save_snippet · delete_snippet

2 tools - e.g. Post a text tweet with markdown-to-Unicode rich text formatting; Post a tweet with a hero banner image (image URL or SVG rendered to PNG)

post_tweet · post_tweet_image

create & write

1 tool - e.g. Store a new post (draft or scheduled); returns its post_id

create_post

update

1 tool - e.g. Patch a stored post (doc, publish_at, recurrence, status)

update_post

delete

1 tool - e.g. Delete a stored post (soft delete by default)

delete_post

Save

1 tool - e.g. Save your per-npub writing Voice

save_voice

Latest releases

v0.40.2 · 2026-08-29

Fixed - an unreadable vault no longer accuses the operator of having no key · The scheduler reported no_operator_llm_key for a key that was vaulted the whole · time, and published the author's fallback text instead of…

v0.40.1 · 2026-08-24

Security - track tollbooth-dpyc 0.88.1 (cryptography floor raised to >=49.0.0) · Picks up the SDK's fix for GHSA-m2h6-j472-rp4c: the X.509 verifier accepted · wildcard DNS SANs, escaping permittedSubtrees. The advisory…

v0.40.0 · 2026-08-24

Fixed - A patron could see the scheduler was stuck, but not why, and could do nothing about it · A patron watching the Scheduler saw a red "Scheduler stalled" dot, no explanation, · and no move to make (#517).…

04 · Who maintains Excalibur MCP

excalibur-mcp is maintained by lonniev. We track 15 MCP servers from lonniev - 15 actively maintained, 6 combined GitHub stars, oldest repo from Feb 2026. Full record: all servers from lonniev.

personalbrain-mcp FastMCP server for TheBrain API - AI access to a personal knowledge graph, Tollbooth-monetized ★ 3

05 · Facts

repository: github.com/lonniev/excalibur-mcp
category: finance - ranked #268 of 318 actively-maintained finance servers as of 2026-09-18.
release cadence: 10+ releases in the last 90 days (latest 2026-08-29)
registry: io.github.lonniev/excalibur-mcp (active, first published 2026-07-16 · 12 versions)

06 · Excalibur MCP FAQ

Is Excalibur MCP still maintained?

Yes - as of 2026-09-18, its last commit was 2026-09-15 and it shipped 10+ releases in the last 90 days. We re-verify nightly.

What can Excalibur MCP do?

With this server connected, an agent can post a text tweet with markdown-to-Unicode rich text formatting, post a tweet with a hero banner image (image URL or SVG rendered to PNG), fetch the connected X account's handle and name for this patron (free), and read one stored post by id (owner-scoped).

How do I install Excalibur MCP?

Run `claude mcp add lonniev-excalibur-mcp --transport http https://excalibur-mcp.fastmcp.app/mcp`. You can also paste the ready-made client config above.

Does Excalibur MCP require authentication?

No - the endpoint accepted our unauthenticated MCP initialize when probed on 2026-09-17; you can connect without credentials.

07 · Alternatives to Excalibur MCP

Alternatives to Excalibur MCP

Maintained finance servers if Excalibur MCP isn't the fit.

Pairs well with

Servers that cover what Excalibur MCP doesn't - only shown when the pairing reason fits the companion.

More finance MCP servers · Saturn Zap · Verantis MCP · Madeonsol · D365FO MCP Server · Magpie MCP

More Python MCP servers · Personalbrain MCP · Lynx · Droste · Dados Brasil · see all