MCP Access – AI-Native Email Workflows

[01 / 07]·Works With

Plugs into your stack

Any MCP-compatible agent — Claude Desktop, Cursor, Windsurf, n8n, Make, and more

Claude

AI Agent

Cursor

IDE

LangChain

Framework

OpenAI

LLM

n8n

Workflow

Windsurf

IDE

LangGraph

Agents

AutoGen

MS Agents

Make

Automation

CrewAI

Multi-agent

Llama

LLM

Gemini

LLM

Claude

AI Agent

Cursor

IDE

LangChain

Framework

OpenAI

LLM

n8n

Workflow

Windsurf

IDE

LangGraph

Agents

AutoGen

MS Agents

Make

Automation

CrewAI

Multi-agent

Llama

LLM

Gemini

LLM

Claude

AI Agent

Cursor

IDE

LangChain

Framework

OpenAI

LLM

n8n

Workflow

Windsurf

IDE

LangGraph

Agents

AutoGen

MS Agents

Make

Automation

CrewAI

Multi-agent

Llama

LLM

Gemini

LLM

Grok

LLM

AutoGen

Multi-agent

Claude

Sonnet

Cursor

Composer

LangChain

Framework

OpenAI

GPT

n8n

Workflow

Windsurf

Code AI

LangGraph

Agents

Make

iPaaS

CrewAI

Multi-agent

Llama

From intent to OTP
in a single tool call

Your AI agent calls create_and_wait_for_otp(). The MCP server holds a long-poll connection, watches for incoming email via Redis pub/sub, extracts the verification code, and returns it — no callbacks, no webhooks, no polling loops.

MCP · Neural Flow

idle

0+

API Calls / Day

0+

Emails / Day

0+

Developers

[03 / 08]·Use Cases

Built for real workflows

Step-by-step guides for the most common disposable email patterns.

All use cases

AI Agent Integration

Give Claude or any LLM agent the ability to sign up for services and verify emails autonomously via MCP.

// Claude Desktop — one config line
"fce-mcp": { "command": "npx", 
  "args": ["-y", "fce-mcp-server"] }

MCPClaude

Guide

OTP Extraction

Extract 4–8 digit codes and verification links from any email — no regex, no maintenance.

const otp = await client.otp.waitFor(inbox);
// "847291"

APISDK

Guide

[04 / 08]·Why MCP

Eleven tools.
Every workflow covered.

MCP tools expose email operations as first-class primitives. No REST endpoints, no webhook glue code — just intent-driven function calls that your agent can use directly.

Agent-native signup testing

Tell Claude to register on any site and extract the OTP. No boilerplate — just intent. The agent handles the entire flow from form submission to email verification.

await claude.runTask(
  "Register on acme.com and verify email"
)

CI / CD pipeline auth

Your test suite needs a fresh inbox per run. One MCP call provisions it and waits for the verification email. No more flaky tests from race conditions.

const { otp } = await mcp.create_and_wait_for_otp({
  timeout: 30
})

Multi-agent orchestration

Nest MCP calls inside larger agent graphs (LangGraph, AutoGen). Each sub-agent gets its own isolated inbox for parallel operations.

// LangGraph node
export const verifyEmail = tool(
  mcp.extract_otp
)

MCP · Neural Flow

idle

[05 / 08]·Tools

Eleven tools.
Infinite workflows.

MCP tools expose email operations as first-class primitives. Each tool is designed for specific email automation tasks — from quick checks to complete signup flows.

get_latest_email

Fetch the latest message from an inbox. Returns sender, subject, body text, OTP, and verification link.

Growth+2× credit

Args

inboxstring

extract_otp

Directly retrieves the latest 4–6 digit code or verification link from the most recent email.

Growth+3× credit

Args

inboxstring

create_and_wait_for_otp🔥 GOLD

Generates a random inbox and holds the connection open until an OTP arrives — complete signup flow in a single tool call.

Growth+5× credit

Args

domainstringoptional

timeoutnumber (10–60)optional

watch_email

Long-polling wait for new emails on an existing inbox. Use when you've already created an inbox and want to wait for the next incoming email.

Growth+10× credit

Args

inboxstring

timeoutnumber (10–60)optional

sincestringoptional

get_messages

Fetches multiple messages from an inbox with pagination support.

Growth+1× credit

Args

inboxstring

limitnumber (1–100)optional

unread_onlybooleanoptional

delete_email

Deletes a specific email from an inbox.

Growth+1× credit

Args

inboxstring

message_idstring

list_inboxes

Lists all inboxes owned by the API key's account.

Growth+1× credit

Args

list_custom_domains

Lists all custom domains associated with the account.

Growth+1× credit

Args

add_custom_domain

Adds a new custom domain to the account.

Growth+1× credit

Args

domainstring

verify_custom_domain

Initiates DNS verification for a custom domain.

Growth+1× credit

Args

domainstring

delete_custom_domain

Deletes a custom domain from the account.

Growth+1× credit

Args

domainstring

Credit multipliers

get_latest_email2×

extract_otp3×

create_and_wait_for_otp5×

watch_email10×

* (other tools)1×

[06 / 08]·Plans

Plan	MCP Access	Ops / min	Concurrent sessions
Free	✗ Blocked	—	—
Developer	✗ Blocked	—	—
Startup	✗ Blocked	—	—
Growth	✓ Included	60	5
Enterprise	✓ Included	200	10

[06 / 08]·Demo

See it in action

Watch create_and_wait_for_otp() run end-to-end. The demo simulates an AI agent calling the MCP tool, waiting for email delivery, extracting the OTP, and returning the result.

AI Agent Terminalready

Agent calls tool

Inbox provisioned

Holding connection

Email arrives

OTP extracted

Returned to agent

Press run demo to simulate the agent flow

[07 / 08]·Setup

Attach to any MCP client

Add the server to Claude Desktop, Cursor, or any MCP-compatible agent framework via npx. Takes less than 30 seconds to configure.

json

{
  "mcpServers": {
    "fce-mcp": {
      "command": "npx",
      "args": ["-y", "fce-mcp-server"],
      "env": {
        "FCE_API_KEY": "your_growth_or_enterprise_api_key"
      }
    }
  }
}

Claude Desktop

Paste the config into claude_desktop_config.json. Restart Claude.

Cursor & Windsurf

Add the npx command in the MCP Servers UI or mcp_config.json.

Kilo CLI

Add to your kilo.json under the mcp section.

Custom Agent

Use any SDK (Python mcp, JS @modelcontextprotocol/sdk) to connect.

[08 / 08]·Cloud MCP

Cloud-based AI agents? No problem.

For cloud-based AI platforms that cannot run local commands (Claude Web, Claude Desktop, Cursor), we provide hosted MCP endpoints. We support two transport protocols: Streamable HTTP (recommended) and SSE (legacy).

Base URL

https://mcp.freecustom.email

Streamable HTTPRecommended

New MCP standard, better for modern clients

SSELegacy

Legacy support for older clients

Endpoint	Method	Transport
/mcp	POST	Streamable HTTP
/mcp	GET	Streamable HTTP
/sse	GET	SSE
/messages	POST	SSE
/authorize	GET	OAuth
/token	POST	OAuth

Two Auth Methods

Direct API Key: Pass via Authorization header or access_token query param
OAuth 2.0: For clients like Claude Web — use your API key as client_id

Quick Start for Claude Web

Open Claude Web (claude.ai) → Settings → Integrations → Add Custom Connector
Name: FreeCustom.Email MCP
URL: https://mcp.freecustom.email/sse
Auth: Your FreeCustom.Email API key as OAuth Client ID

Model Context Protocolfor email automation

Plugs into your stack

From intent to OTPin a single tool call

Built for real workflows

Eleven tools.Every workflow covered.

Eleven tools.Infinite workflows.

See it in action

Attach to any MCP client

Cloud-based AI agents? No problem.

Two Auth Methods

Quick Start for Claude Web

Model Context Protocol
for email automation

From intent to OTP
in a single tool call

Eleven tools.
Every workflow covered.

Eleven tools.
Infinite workflows.