@extenshi/mcp

A Model Context Protocol server that brings the Extenshi extension catalog — search, security analysis, market research, and pre-publish scanning — into your AI tools (Claude Code, Claude Desktop, Cursor, …).

It runs locally over stdio, so there's nothing to host. It reuses your existing Extenshi API key (the same one @extenshi/cli uses) and talks to the public Extenshi backend on your behalf.

Get an API key

An API key is required — every tool refuses to run without one, and the backend enforces it too.

1. Sign up at https://auth.extenshi.io/signup
2. Create a key at https://dojo.extenshi.io/api-keys
3. Provide it via the EXTENSHI_API_KEY environment variable (or run extenshi login, which the MCP server reads from ~/.extenshi/config.json).

Configure your MCP client

{
  "mcpServers": {
    "extenshi": {
      "command": "npx",
      "args": ["-y", "@extenshi/mcp@latest"],
      "env": { "EXTENSHI_API_KEY": "ek_…" }
    }
  }
}

Tools

| Tool | What it does | Cost | | --- | --- | --- | | search_extensions | Hybrid search across Chrome/Firefox/Edge with filters (store, category, pricing, rating, risk, permissions) | 1 read | | get_extension | Full catalog detail for one extension by numeric catalog ID | 1 read | | get_security | Risk score + finding counts + top grouped findings (reads existing scans) | 1 read | | get_related_extensions | Similar / competing extensions for competitive analysis | 1 read | | market_overview | Catalog-wide market intelligence with no args (totals, store split, category tree, and the extended breakdown — MV2/MV3, sensitive permissions, risk tiers, trader status, recency, reviews); pass a query to scope facets to a search | 1 read | | search_docs | Search the Extenshi docs + @extenshi/cli reference so the assistant can quote exact commands | Free (no key) | | scan_extension | Pre-publish security scan of a local artifact (.zip/.crx/.xpi), with live progress | 1 monthly-quota scan | | publish_extension | Publish to Chrome/Firefox/Edge with your own store credentials (fully local) | Free |

Every plan includes monthly reads and scans — the Free plan has 25 reads and 5 scans per month, paid plans go up to 10,000 reads and 1,000 scans. Quotas reset on the 1st (UTC). Manage your plan at https://dojo.extenshi.io/billing.

Configuration

| Env var | Default | Purpose | | --- | --- | --- | | EXTENSHI_API_KEY | — | Your ek_… developer key (required) | | EXTENSHI_BFF_URL | https://bff.extenshi.io | Catalog read API base URL | | EXTENSHI_API_URL | https://scan.extenshi.io | Scan backend base URL | | EXTENSHI_DOCS_URL | https://docs.extenshi.io | Docs base URL for search_docs |

Develop

yarn build            # tsc -> dist/
# Inspect locally:
EXTENSHI_API_KEY=ek_… npx @modelcontextprotocol/inspector node dist/index.js

Publishing is handled by ./scripts/publish.sh (npm Automation token from Infisical; DRY_RUN=1 ./scripts/publish.sh to validate). Requires Node ≥20.