MCP servers

Nearly every agent ecosystem stores MCP servers in the same JSON shape, so one normaliser covers all of them.

The shape Gate reads

{
  "mcpServers": {
    "github": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-github@2025.4.8"],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "${env:GITHUB_TOKEN}"
      }
    },
    "vendor": {
      "type": "http",
      "url": "https://mcp.vendor.example/v1",
      "headers": { "Authorization": "Bearer ${env:VENDOR_TOKEN}" }
    }
  }
}

VS Code uses servers instead of mcpServers; Codex uses [mcp_servers.name] in TOML. Gate reads all three.

Transports

What Gate extracts

From each server definition:

• Credentials: in env, in args, in headers, and in the URL itself. Detected, classified by type, and redacted at the boundary. A value like ${env:TOKEN} is recorded as a credential the agent holds, but not as a leak: referencing a secret is the fix, not the problem.
• Filesystem grants: any argument or environment value that looks like a path, classified by scope and checked against known credential directories.
• Production indicators: prod, production, prd, live, or a live-mode payment key, matched on word boundaries so product_catalog does not trip it.
• Tools: for recognised packages, the real tool list.

Known servers

Gate recognises 52 server classes, covering 194 individually mapped tools. The table is split into two kinds of match:

Exact match: a specific package whose tool list Gate knows. Tools are enumerated as fact:

2 MCP servers
14 exposed tools

Category match: Gate recognises the kind of server but not the exact package. It records a capability posture instead of inventing tools:

GATE005  db
         db: PostgreSQL server; tool set not enumerated, capabilities
         inferred from the server type

This distinction is why Gate's counts can be trusted. Enumerating tools a server might not have would inflate every headline number, and a security tool with inflated numbers is a security tool nobody believes.

Contributing a mapping

The known-server table is Gate's accumulating asset: every entry turns a guess into a fact, for everyone. Adding one is the highest-value contribution to Gate.

Several of the original @modelcontextprotocol/server-* packages were archived in 2025, with vendors taking over the important ones. GitHub now maintains github/github-mcp-server. Gate still matches the archived names: they are still pinned in configuration files, and a scanner has to find what is running.

{
  id: 'linear',
  label: 'Linear',
  match: ['mcp.linear.app'],
  fuzzyMatch: ['linear-mcp'],
  tools: {
    create_issue: ['write', 'communicate'],
    update_issue: ['write'],
    search_issues: ['search', 'read'],
    delete_issue: ['delete'],
  },
  defaultCapabilities: ['read', 'search', 'write'],
}

Only put a package in match if you have read that server and the tool list is right. Everything else goes in fuzzyMatch.