# Fidro Now Has an MCP Server: Score Signups and Manage Your Blocklist From ChatGPT, Claude and Cursor > Connect Fidro to any MCP-compatible assistant and ask it whether a signup looks risky, where an IP is, how much quota is left, or to block an email with a reason. Works on every plan, including Free. **Author:** Matt King | **Published:** September 7, 2026 | **Category:** Product --- Fidro now ships a Model Context Protocol server. Point ChatGPT, Claude, Cursor, VS Code, Codex or Claude Code at `https://fidro.io/mcp`, approve it once, and your assistant can score signups, look up IPs, check your quota and manage your blocklist against your real account. It is on every plan, including Free, from today. The [MCP page](/mcp) has the endpoint, a one-minute setup for each client and the full tool list. The [MCP guide](/docs/guides/mcp) goes deeper. This post is about why we built it and what it is useful for. ## Why an MCP server Fraud decisions rarely get made inside the fraud tool. They get made in a support thread, a Slack channel, a chargeback dispute, or the editor where someone is wiring up the signup form. Fidro's API answers the question "is this signup risky?" in under 200 milliseconds, but the person asking usually has to open a dashboard, paste the email and the IP into the playground, and carry the answer back to wherever the decision is being made. MCP is an open standard that lets an AI assistant discover and call a service's tools directly. With the Fidro server connected, the assistant scores the signup itself, reads the individual checks, and answers from live data in the conversation you are already having. When the answer is "block it", the assistant can add the email to your blocklist with the reason attached, so the next attempt is caught at the API. There is no prompt to paste. Every tool is discovered on connection; the only configuration is the URL and a sign-in. ## What the server exposes Six tools, deliberately few: - **`validate_signup`** scores an email address, an IP address, or both, the same way the `/validate` endpoint does: disposable and role email detection, VPN, proxy, Tor and datacenter detection, country mismatch and your own blocklists. It returns the 0 to 100 score, an allow, review or block recommendation and each check that fired. - **`lookup_ip`** returns country, region, city, timezone and network details for one IP without scoring it. - **`get_account_status`** shows your plan, the live requests used this month, the remaining quota and whether blocklists are available. - **`list_blocklist`**, **`add_to_blocklist`** and **`remove_from_blocklist`** read and change the emails, IPs, domains and card fingerprints your account blocks. These need Starter or above, as they do through the API. Each tool is annotated so the assistant knows which are read-only and which change state, and every call is scoped to the account you signed in with. ## Use cases These are the workflows we designed the tool set around. ### Answer "does this signup look right?" where the question is asked > "Is alice@mailinator.com signing up from 185.220.101.1 risky?" The assistant calls `validate_signup` with both values and explains the result: disposable email domain, Tor exit node, score 91, block. Because it can read the individual checks rather than only the score, it can tell you *why*, which is what a support agent or a founder reviewing a trial actually wants to know. ### Investigate a chargeback or an abuse report > "Here is the IP from the dispute. Where is it, and is it hiding behind anything?" `lookup_ip` gives the location and network, `validate_signup` says whether it is a VPN, proxy or datacenter address and whether it matches the country on the card. Two questions that used to mean two tabs and a copy-paste are one sentence. ### Keep the blocklist current from the conversation where the decision is made > "Block chargebacks@example.com, reason 'disputed twice', severity 9." `add_to_blocklist` creates the entry with the reason attached. The next signup or payment from that address is flagged by the API without anyone touching the dashboard. Ask "show me everything on our blocklist with severity 8 or higher" and `list_blocklist` filters it for you. Removing an entry needs an explicit confirmation, so the assistant will show you what it is about to delete and ask first. ### Build the integration with the live API next to you In Cursor, VS Code or Claude Code the assistant already has your signup handler open. Ask it to "wire up Fidro on the register endpoint and show me what a disposable email returns." It calls `validate_signup` against your real account, sees the exact response shape, and writes the handler to match. The docs, the live response and the code are in one place, and the example calls land in your audit log like any other request. ### Check a batch without writing a script Paste twenty signups from this morning's export and ask which ones to review. The assistant calls `validate_signup` for each and returns a ranked list. Each call is a live request and counts against your quota, so `get_account_status` first is a reasonable habit; the assistant can do that for you too. ### Know where you stand before a launch > "How much of my Fidro quota is left this month?" `get_account_status` answers with the plan, the requests used and the remaining allowance. No quota is spent asking. ## What it will not do Some boundaries were deliberate. - **OAuth only.** The MCP endpoint refuses API keys. You approve an assistant once on a consent screen; it receives a token limited to your account, and the key you use in production never leaves the dashboard. - **Account scoped.** A connected assistant sees the account you signed in with and nothing else. - **No account changes.** It cannot create or delete API keys, change your plan or touch billing. - **Confirmation for the irreversible tool.** `remove_from_blocklist` requires `confirm: true`, which a well-behaved assistant only sends after checking with you. - **Quota applies.** Validations and lookups made through an assistant are live requests. They count against the monthly quota and appear in the audit log under a key called "Connected assistants (MCP)", so nothing happens off the books. - **Rate limited.** The server has its own limiter, so a runaway agent loop cannot burn through your allowance in one go. Access tokens expire after an hour and refresh silently for up to 90 days. Every connected assistant is listed under Connected assistants on the [API keys page](/app/api-keys), with a Disconnect button that revokes it immediately. ## Getting connected Every client is covered on the [MCP page](/mcp) and in the [MCP guide](/docs/guides/mcp): ChatGPT, Claude, Claude Code, Codex, Cursor, VS Code, Gemini CLI and Windsurf. Each one needs the URL and a sign-in. If you are not a customer yet, the [free plan](/register) includes 200 validations a month and MCP access from the first minute, no card required. --- ## Frequently Asked Questions ### What is the Fidro MCP server? It is a remote Model Context Protocol server at fidro.io/mcp that gives an AI assistant access to your Fidro account. Once connected, ChatGPT, Claude, Cursor, Codex or Claude Code can score a signup for fraud risk, look up an IP address, check your plan and quota, and read, add to or remove from your blocklist, all from a plain-language request. ### Which AI assistants work with Fidro MCP? Any client that supports remote MCP servers over Streamable HTTP: ChatGPT, Claude on claude.ai and Claude Desktop, Claude Code, Cursor, VS Code with GitHub Copilot, Codex CLI, Gemini CLI and Windsurf. The MCP guide in the docs has a setup section for each one. ### Does MCP access cost extra or count against my quota? MCP is included on every plan, including Free. Validations and IP lookups made through an assistant are live requests, so they count against your monthly quota exactly like a call to the API. Reading your account status and working with the blocklist do not count. The three blocklist tools need Starter or above, the same as the API. ### Can I use my API key to connect an assistant? No. The MCP server only accepts OAuth. You approve the assistant once on a consent screen in your browser, it receives a token limited to your account, and you can revoke it from the API keys page at any time. API keys are for your application code and are refused by the MCP endpoint. ### Can an assistant delete things or change my billing? It cannot create or delete API keys, change your plan or touch billing. The only irreversible tool, remove_from_blocklist, refuses to run unless the assistant explicitly confirms after checking with you. Everything it does appears in your audit log under a key called Connected assistants (MCP).