tc39-mcp
Independent MCP server for the TC39 specs (ECMA-262 + ECMA-402): clauses, search, diffs, history.
MCP server · by xyzzylabs
About
tc39-mcp is an MCP server published by xyzzylabs. Marketplaces we read that list it: 1 (Official MCP Registry). We first saw it on 2026-10-11 and have recorded no change since. As of our marketplace pass on 2026-10-14.
What it asks for
- Runs remotely
None of the marketplaces we read publishes its tools or the settings it asks for.
What it declares, asks for and runs, in full
Only install plugins from developers you trust. We list what marketplaces publish and do not test plugins.
Package
npm tc39-mcp (tc39-mcp on npm)
- npm downloads/week: 556 (2026-10-13)
- npm downloads/month: 808 (2026-10-13)
- Latest version on npm: 0.6.5, published 2026-10-08
No known vulnerabilities in OSV for 0.6.4 (checked 2026-10-13)
npm facts come from the public npm registry (registry.npmjs.org, api.npmjs.org). Each figure is the registry's own and is never added to another. A registry that publishes no figure shows none: no number is not zero. Vulnerability records come from OSV.dev (CC BY 4.0) and concern the declared version only; a listing that declares no version gets no answer. We do not scan code.
Works with
- Claude Code
- Codex
- Cursor
- VS Code
- Copilot CLI
A one-click link opens the client, which asks you to confirm before it adds the server.
From the marketplaces that list it and the MCP transport it declares, as each client documents them. We do not test plugins.
Connect
Commands and configs built only from what its marketplaces declare. We do not run them for you and do not test plugins.
As a remote MCP server
Built from what Official MCP Registry declares.
claude mcp add --transport http tc39-mcp https://mcp.xyzzylabs.ai/tc39/mcp[mcp_servers.tc39-mcp]
url = "https://mcp.xyzzylabs.ai/tc39/mcp"{
"mcpServers": {
"tc39-mcp": {
"url": "https://mcp.xyzzylabs.ai/tc39/mcp"
}
}
}Where it is published
| Marketplace | Status | Version | Figures | Verified | First seen |
|---|---|---|---|---|---|
| Official MCP Registry (Open the registry record) | Listed | 0.6.4 | Downloads/month (npm): 808 Downloads/week (npm): 556 Forks (GitHub): 0 Stars (GitHub): 2 |
Not marked |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
What changed
Nothing has moved on this plugin since we started watching it.
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Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.