agentguard-mcp

# agentguard-mcp **MCP server for [`@mukundakatta/agentguard`](https://www.npmjs.com/package/@mukundakatta/agentguard).** Lets Claude Desktop, Cursor, Cline, Windsurf, Zed, or any other MCP client check whether a URL is allowed under a network-egress policy before any fetch. ```bash npx -y @mukundakatta/agentguard-mcp ``` Three tools: - **`check_url`** — single URL check: returns `{ allowed, reason }` without making any actual request. - **`check_urls_batch`** — batch check with per-URL decisions plus a summary. - **`validate_policy`** — sanity-check a policy spec for empty allowlists, overly broad `*` wildcards, and malformed host patterns. ## Add to your client ### Claude Desktop Edit `~/Library/Application Support/Claude/claude_desktop_config.json` (macOS) or `%APPDATA%\Claude\claude_desktop_config.json` (Windows): ```json { "mcpServers": { "agentguard": { "command": "npx", "args": ["-y", "@mukundakatta/agentguard-mcp"] } } } ``` Same shape for Cursor (`~/.cursor/mcp.json`), Cline, Windsurf, Zed. ## Tool examples **`check_url`:** ```json { "url": "https://api.openai.com/v1/chat", "policy": { "allow": ["api.openai.com", "*.anthropic.com"] } } ``` Returns: ```json { "allowed": true, "reason": "matched_allowlist", "detail": null } ``` **`check_urls_batch`:** ```json { "urls": [ "https://api.openai.com/v1/chat", "https://evil.example.com/leak" ], "policy": { "allow": ["api.openai.com"] } } ``` Returns: ```json { "results": [ { "url": "https://api.openai.com/v1/chat", "allowed": true, ... }, { "url": "https://evil.example.com/leak", "allowed": false, "reason": "not_in_allowlist", ... } ], "summary": { "total": 2, "allowed_count": 1, "denied_count": 1 } } ``` **`validate_policy`:** ```json { "policy": { "allow": ["*", "https://api.example.com", "api.example.com/v1"] } } ``` Returns issues for the `*` wildcard, the scheme prefix, and the path suffix — common mistakes when first writing a policy. ## Why a separate MCP server `@mukundakatta/agentguard` is a zero-dependency JavaScript library. This MCP server makes its decision engine accessible from any MCP-aware AI assistant: ask Claude "does my agent's tool list pass this firewall?" or "which of these 50 URLs would my policy block?" and the assistant calls these tools directly. Note: this MCP server only **checks** URLs — it does not actually wrap fetch or block real requests. For runtime enforcement, use `@mukundakatta/agentguard` directly inside your Node process. ## Sibling MCP servers Part of the agent-stack series: - [`@mukundakatta/agentfit-mcp`](https://www.npmjs.com/package/@mukundakatta/agentfit-mcp) — *Fit it.* - [`@mukundakatta/agentguard-mcp`](https://www.npmjs.com/package/@mukundakatta/agentguard-mcp) — *Sandbox it.* (this) - [`@mukundakatta/agentsnap-mcp`](https://www.npmjs.com/package/@mukundakatta/agentsnap-mcp) — *Test it.* - [`@mukundakatta/agentvet-mcp`](https://www.npmjs.com/package/@mukundakatta/agentvet-mcp) — *Vet it.* - [`@mukundakatta/agentcast-mcp`](https://www.npmjs.com/package/@mukundakatta/agentcast-mcp) — *Validate it.* ## License MIT