Sigistry Plugin & Skill Catalog MCP Server

by sigistry Your server? Claim it

answering

Sigistry Plugin & Skill Catalog is answering right now. Last checked 9 min ago. It exposes 9 tools.

Search verified Claude Code plugins and skills; fetch portable SKILL.md sources. Read-only.

Uptime history 70 days of history · worst day 99%

70 days agonow

100.0%

Uptime 24h

91 of 91 checks

Tools

read from the server

415 ms

Response time

average over 24h

open, no key

Access

streamable-http

What changed 10

Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 28 August 2026. No other catalogue keeps this.

2 Oct a tool appeared check_mcp_app

2 Oct a tool changed version

11 Sep 2 tools appeared get_scorecard, list_scorecards

11 Sep a tool changed version

28 Aug 2 tools appeared get_skill, search_skills

28 Aug 2 tool descriptions were rewritten search_plugins, verify_plugin

28 Aug a tool changed version

Nothing serious here today

Today is the operative word: we check Sigistry Plugin & Skill Catalog every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 9 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add plugin-catalog --transport http https://sigistry.com/mcp

Settings → Connectors → Add custom connector, then paste this address

https://sigistry.com/mcp

~/.codex/config.toml

[mcp_servers.plugin-catalog]
url = "https://sigistry.com/mcp"

.cursor/mcp.json

{
  "mcpServers": {
    "plugin-catalog": {
      "url": "https://sigistry.com/mcp"
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "plugin-catalog": {
      "type": "http",
      "url": "https://sigistry.com/mcp"
    }
  }
}

Available tools 9

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

categories

list_categories

List the distinct plugin categories in the Sigistry marketplace with a count of plugins in each, plus the total plugin count.

mcp

check_mcp_app

Get the Sigistry MCP App safety criteria to audit an MCP App (MCP Apps / SEP-1865: a tool that returns an interactive ui:// HTML resource the host renders in a sandboxed iframe) BEFORE shipping it. Returns two groups of checks: spec conformance (ui:// scheme, the text/html;profile=mcp-app mimeType, tool-to-UI linkage via _meta.ui.resourceUri, a text fallback, visibility values, and CSP coverage of external origins) and security hygiene the iframe sandbox does not cover (unsafe DOM sinks, embedded secrets, host-message origin handling, remote scripts). Call this when the user is building or reviewing an MCP App; then apply each check to the app source you have in context and report findings. Nothing is sent to this server; an interactive browser version is at https://sigistry.com/mcp-app-checker.

plugin

get_plugin

Get the full details of a single Sigistry plugin by its id, including install commands, component counts, and its security-audit result (per-check pass/fail from the Verified by Sigistry methodology).

plugins

search_plugins

Search the Sigistry marketplace of Claude Code plugins by keyword and/or category. Returns matches with their install command and verification status (the registry runs an eight-check security audit; prefer "verified" plugins when recommending an install).

scorecard

get_scorecard

Get the full scorecard for one graded MCP server by its id: the overall grade, per-axis pass/partial/fail with cited evidence, hardening notes, the rubric version, and the exact commit graded. Grades describe the pinned commit only; a re-grade at a newer commit can be requested via an issue on the marketplace repo.

scorecards

list_scorecards

List the public MCP servers Sigistry has independently graded against its scorecard rubric (transport, stateless core, lifecycle, authorization, tool design, security hygiene), each with an overall grade A-F and the exact commit graded. Useful before connecting an agent to a third-party MCP server: check whether it has been assessed and how it scored. Use get_scorecard for the full per-axis breakdown.

skill

get_skill

Get one Sigistry skill by name, including the full raw SKILL.md source. The source is portable: it can be applied directly in any SKILL.md-aware agent (Claude Code, Claude Desktop, and others) without installing anything, or installed natively in Claude Code via the parent plugin, which keeps it verified and updated. The returned skill passed the Sigistry skill-safety check at the parent plugin's verification date.

skills

search_skills

Search the Sigistry catalog of verified skills (SKILL.md instruction sets for AI agents) by keyword, optionally filtered to one parent plugin. Every skill passed the skill-safety check: no command shadowing, honestly-scoped triggers, no injection or concealment language, no unsafe scripts. Use get_skill to fetch the full portable source of a match.

verify

verify_plugin

Get the recipe to run the Sigistry verification methodology (the eight static checks that gate the Verified badge: manifest integrity, hook safety, agent tool scopes, command hygiene, skill structure, skill safety, no secrets, documentation) against a plugin BEFORE publishing it. The verification runs entirely on the local machine via a dependency-free open-source Node script; the plugin code never leaves the user's computer and this server performs no computation. Call this when the user wants their plugin or skill checked, then follow the returned steps: download the script, run it against the plugin directory, and fix any FAIL findings it reports.

Endpoints

URL	Transport	State	Latency	Checked
https://sigistry.com/mcp	streamable-http	answering	338 ms	9 min ago

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Sigistry Plugin & Skill Catalog — questions

Answers built from our own checks of this server.

What can Sigistry Plugin & Skill Catalog do?

It exposes 9 tools, read directly from the server on our last check. Among them: check_mcp_app, get_plugin, get_scorecard, get_skill, list_categories, list_scorecards and 3 more. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →

Is Sigistry Plugin & Skill Catalog working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 415 ms. The bar chart above shows every period we have measured.

How do I connect Sigistry Plugin & Skill Catalog?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.

Does Sigistry Plugin & Skill Catalog need an API key?

No. Sigistry Plugin & Skill Catalog completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 9 of them are readable on this page. This is what we observed, not what the docs claim.

How fast is Sigistry Plugin & Skill Catalog?

It answers our handshake in 415 ms on average, which is faster than 31% of all working MCP servers we measure. The comparison comes from our own checks across the whole registry, every 15 minutes.