tc39 MCP Server
by xyzzylabsio.github.xyzzylabs/tc39-mcpv0.6.4
Independent MCP server for the TC39 specs (ECMA-262 + ECMA-402): clauses, search, diffs, history.
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Active1d ago
Install tc39 MCP server
Install in Claude Code
claude mcp add tc39 -- npx -y tc39-mcpInstall in Cursor
{
"mcpServers": {
"tc39": {
"command": "npx",
"args": [
"-y",
"tc39-mcp"
]
}
}
}Add to ~/.cursor/mcp.json (global) or .cursor/mcp.json (project).
Install in Claude Desktop
{
"mcpServers": {
"tc39": {
"command": "npx",
"args": [
"-y",
"tc39-mcp"
]
}
}
}Settings → Developer → Edit Config (claude_desktop_config.json), then restart.
Install in VS Code
{
"servers": {
"tc39": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"tc39-mcp"
]
}
}
}Add to .vscode/mcp.json in your workspace.
Install in Windsurf
{
"mcpServers": {
"tc39": {
"command": "npx",
"args": [
"-y",
"tc39-mcp"
]
}
}
}Add to ~/.codeium/windsurf/mcp_config.json.
Remote endpoints
- streamable-http
https://mcp.xyzzylabs.ai/tc39/mcp
Freshness
Active — last maintenance signal 1d ago. The newest of the signals below sets the band.
Last commit (default branch)
2026-10-08 · 1d ago · GitHub
Latest release
2026-10-07 · 2d ago · GitHub · v0.6.4
Package published
no data · npm/PyPI
Registry entry updated
2026-10-07 · 2d ago · official registry · v0.6.4
FAQ
›How do I install the tc39 MCP server in Claude Code?
Run: claude mcp add tc39 -- npx -y tc39-mcp. For Cursor, VS Code, Claude Desktop and Windsurf, use the install tabs above.
›Does tc39 require an API key?
No required environment variables are declared in its published metadata.
›Can I use tc39 as a remote (hosted) MCP server?
Yes — it offers both a hosted endpoint and a local stdio package.
›Is tc39 in the official MCP registry?
Yes, as io.github.xyzzylabs/tc39-mcp.