Why FreeCustom.Email Is the Only Disposable Email API With an Official CLI (2026)

If you have ever built an application that sends verification emails, run automated integration tests, or set up a CI/CD pipeline that needs to handle email-based authentication flows, you have almost certainly reached for a disposable email service. And you have almost certainly had the same frustrating experience: clunky web UIs, undocumented APIs, rate limits that kill your tests at 2 AM, and zero tooling beyond a basic HTTP endpoint.

That experience is what FreeCustom.Email was built to fix. As of 2026, we are the only disposable and temporary email provider in the world to ship an official, installable CLI tool — alongside a full REST API, official SDKs for JavaScript/TypeScript and Python, WebSocket real-time streaming, automatic OTP extraction, and a growing ecosystem of automation integrations including AI agent support.

This post covers what that actually means for you, why it matters, and how to use all of it.

The State of Disposable Email Tooling in 2026

The disposable email space is crowded with services that range from simple open-source scripts to enterprise-grade API platforms. Yet virtually all of them share one blind spot: they treat the terminal as an afterthought.

Here is the reality of developer tooling across the major providers as of March 2026:

Make and Zapier integrations are announced for Q2 2026.

The gap is not subtle. No other provider in this space has invested in a CLI, let alone official language SDKs, real-time WebSocket delivery, or no-code automation connectors. FreeCustom.Email is uniquely positioned in this regard.

What Is the fce CLI?

The fce CLI (short for FreeCustom.Email) is a native binary written in Go, distributed for macOS, Linux, and Windows. It is the first and only official command-line tool for a disposable email service, and it turns what used to be a multi-step API workflow into a single terminal command.

Install in one line

bash

curl -fsSL freecustom.email/install.sh | sh

Or via your preferred package manager:

bash

# macOS / Linux
brew tap DishIs/homebrew-tap && brew install fce

# Windows (Scoop)
scoop bucket add fce https://github.com/DishIs/scoop-bucket && scoop install fce

# Windows (Chocolatey)
choco install fce

# npm (all platforms)
npm install -g fcemail

# Go
go install github.com/DishIs/fce-cli@latest

Once installed, authenticate once with your browser — your API key is created automatically and stored securely in your OS keychain:

bash

fce login
# Opens browser → sign in → key saved to keychain automatically
# Keys always reflect your current plan — no manual copying needed

The full command surface

fce dev: The Fastest Way to Start

The fce dev command combines fce inbox add random and fce watch into a single command — you get a disposable inbox and a live email stream in under two seconds:

bash

fce dev

  ·  Temporary inbox: dev-fy8x@ditcloud.info
  ✓  Watching for emails...

  ✓  Watching dev-fy8x@ditcloud.info   GROWTH
  ·  Waiting for emails… (press Ctrl+C to stop)

────────────────────────────────────────────────────
  ID    JpW3DImT3
  FROM  "Dishant Singh" <dishupandey57@gmail.com>
  SUBJ  Your OTP for FCE: 212342
  TIME  20:19:54
────────────────────────────────────────────────────

No setup. No configuration. No web UI. Just a terminal and one command.

Compare this to any other provider where the equivalent workflow is: open a browser, navigate to the service, copy an email address, paste it into your app, switch back to the browser, wait for the inbox to refresh, manually copy the OTP, paste it into your terminal. That is a 6-step manual process versus fce dev.

Real-Time Email Streaming with WebSocket

Most disposable email APIs are polling-based — you call GET /messages on a loop until something arrives. This is slow, wasteful, and a nightmare for CI pipelines with hard timeouts.

fce watch opens a persistent WebSocket connection and delivers emails to your terminal the moment they arrive — under 200ms from send to screen. The CLI handles automatic reconnection if the connection drops. No babysitting required.

This capability is available on Startup plan and above and is not offered by any other disposable email provider's tooling.

OTP Extraction: No Regex Required

One of the most common use cases for disposable email in development is extracting one-time passwords from verification emails. Before fce otp, this meant fetching the raw email body, writing a regex to find the code, handling different email formats from different services, and breaking when the format changes.

fce otp eliminates all of this:

bash

fce otp dev-fy8x@ditcloud.info

────────────────────────────────────────────────
  OTP
────────────────────────────────────────────────

  OTP   ·  212342
  From  ·  "Dishant Singh" <dishupandey57@gmail.com>
  Subj  ·  Your OTP for FCE: 212342
  Time  ·  20:19:54

In a script, capture just the code:

bash

OTP=$(fce otp dev-fy8x@ditcloud.info | grep "OTP   ·" | awk '{print $NF}')
echo "Got: $OTP"
# Got: 212342

Available on Growth plan and above. Works identically via the REST API and both official SDKs.

The Official SDKs

JavaScript / TypeScript

bash

npm install freecustom-email

typescript

import { FreecustomEmailClient } from 'freecustom-email';

const client = new FreecustomEmailClient({ apiKey: process.env.FCE_API_KEY });

await client.inboxes.register('test@ditmail.info');
const otp = await client.otp.waitFor('test@ditmail.info');
console.log(otp); // '212342'

Full TypeScript types, ESM + CommonJS dual build, auto-reconnect WebSocket, and typed error classes included.

Python

bash

pip install freecustom-email

python

from freecustom_email import FreeCustomEmail
import asyncio, os

client = FreeCustomEmail(api_key=os.environ["FCE_API_KEY"])

async def main():
    await client.inboxes.register("test@ditmail.info")
    otp = await client.otp.wait_for("test@ditmail.info")
    print(otp)  # '212342'

asyncio.run(main())

Both async and sync modes supported. Full type annotations and dataclass response models included.

CI/CD Integration

In CI runners where there is no browser for fce login, set your API key as a secret environment variable. Get it from the dashboard after running fce login locally — it automatically reflects your current plan.

yaml

- name: E2E email verification test
  env:
    FCE_API_KEY: ${{ secrets.FCE_API_KEY }}
  run: |
    curl -fsSL freecustom.email/install.sh | sh
    INBOX=$(fce inbox add random)
    curl -s -X POST https://myapp.com/signup -d "email=$INBOX"
    OTP=$(fce otp $INBOX | grep "OTP   ·" | awk '{print $NF}')
    curl -s -X POST https://myapp.com/verify -d "otp=$OTP"

For a complete CI/CD guide, see How to Automate Email Verification Testing in CI/CD Pipelines (2026).

Automation Ecosystem

For a deep dive into using AI agents, see Automate Email Workflows with AI Agents in 2026.

Pricing

Credits are available à la carte and never expire — top up once, use any time.

Frequently Asked Questions

Is the fce CLI open source? Yes. Source at github.com/DishIs/fce-cli under the MIT License.

Does fce login require a paid plan? No. fce login works with every plan including free. It creates your API key automatically and saves it to your OS keychain.

Which OS keychain does fce use? macOS Keychain on macOS, Windows Credential Manager on Windows, and Linux Secret Service (libsecret) on Linux.

Can I use fce in Docker containers? Yes — set FCE_API_KEY as an environment variable. The CLI detects it and skips interactive login.

Does the CLI support custom domains? Yes. fce domains lists all domains available on your plan. Custom domain registration is available on Growth and above.

Is OTP extraction reliable across different email formats? The extraction engine handles numeric codes, alphanumeric tokens, magic links, and more. It has been tested across hundreds of email service formats and does not rely on simple regex.

What happens to temp inboxes when I stop fce dev? Ctrl+C disconnects the WebSocket but does not delete the inbox. Clean up with fce inbox remove <addr>.

How is this different from just using the REST API directly? The CLI wraps the API with authentication management, credential storage, real-time WebSocket handling, OTP parsing, and human-friendly output. For scripting and terminal use it is significantly faster than raw HTTP calls.

What's Next

Track releases at github.com/DishIs/fce-cli/releases and stay up to date with fce update. The upcoming Make and Zapier integrations will bring the same capabilities to no-code workflows in Q2 2026.

Related reading:

• How to Automate Email Verification Testing in CI/CD Pipelines (2026)

• AI Agent Email Automation with OpenClaw and n8n (2026)

• FreeCustom.Email vs Mailinator vs Guerrilla Mail: Disposable Email API Comparison (2026)