Use asms with Windsurf

Add asms to Windsurf's Cascade agent. It can then get verification codes, rent numbers and read their SMS while it works on your code.

Set it up Get an API key

One API key Codes from $0.50, refunded if none arrives Asks before it spends

Windsurf · asms connected

Get me a US number for Telegram and give me the code when it arrives.

asms · get_pricingin stock

US Telegram numbers are in stock at the listed price, and you're only charged if a code arrives. Order one?

Yes, go ahead.

asms · create_otp_order+1 347 •••-••18

asms · poll_smscode received

Your number is +1 347 •••-••18 and the Telegram code is 504913.

What you can ask Windsurf

Once asms is connected, Windsurf can order numbers, read the SMS they receive and check your account, all paid from your asms wallet.

Get a verification code

“Order a UK number for WhatsApp and wait for the code.”

Rent a number you keep

“Rent a US number for a month for our app's SMS login tests, and show me any texts it gets.”

Check the account

“What's my asms balance, and which orders are still waiting for a code?”

Setup

You need an asms API key: create one in your dashboard and keep it in the ASMS_API_KEY environment variable.

The quick way: paste a prompt

Paste this into Windsurf. It reads this page and follows the steps for agents below.

prompt

Connect the asms MCP server to Windsurf by following the steps for AI agents at https://asms.ai/agents/windsurf. My asms API key is in the ASMS_API_KEY environment variable; don't print it.

Or step by step

1
Open the MCP config
In Cascade, open the … menu → MCPs, then edit the raw config (mcp_config.json).

Add asms

mcp_config.json

{
  "mcpServers": {
    "asms": {
      "serverUrl": "https://asms.ai/mcp",
      "headers": {
        "Authorization": "Bearer ${env:ASMS_API_KEY}"
      }
    }
  }
}

3
Check it
Back in Cascade's MCPs menu, asms should show its tools with the switch on.

For AI agents reading this page

If a user asked you to connect asms to Windsurf, follow these steps in order.

Check whether the ASMS_API_KEY environment variable is set, without printing its value. If it is not set, ask the user to create a key at https://asms.ai/dashboard#api-keys and set ASMS_API_KEY, then stop until they confirm.
Register the server: add an "asms" entry with serverUrl https://asms.ai/mcp and the header Authorization: Bearer ${env:ASMS_API_KEY} to Cascade's mcp_config.json.
Check it worked: ask the user to open Cascade's MCPs menu and confirm asms is on with its tools.
Start read-only: call get_balance, then get_pricing or get_rental_offers, and report what you found.
Before any tool that spends from the wallet (create_otp_order, rent_number), tell the user the price and wait for their OK.
Never create an asms account or API key, top up the wallet, or approve a sign-in on the user's behalf, and never print the key.

Reference

MCP endpoint	https://asms.ai/mcp
Transport	Streamable HTTP (stateless)
Auth	OAuth sign-in with asms, or the header Authorization: Bearer <ASMS_API_KEY>
REST API	https://asms.ai/api-docs
For LLMs	https://asms.ai/llms.txt

Tools

Tool	What it does	Needs your OK?
`get_balance`	Wallet balance	No
`get_pricing`	Verification code prices	No
`get_inventory`	Verification number stock	No
`create_otp_order`	Order a verification number	Yes
`poll_sms`	Check for the verification code	No
`list_active_orders`	List verification orders	No
`cancel_order`	Cancel a verification order	Yes
`get_rental_offers`	Number rental prices	No
`rent_number`	Rent a phone number	Yes
`list_rentals`	List rented numbers	No
`read_rental_sms`	Read a rented number's SMS	No
`cancel_rental`	Cancel a rental for a refund	Yes

Other agents and tools

Claude Code Claude Codex ChatGPT Cursor VS Code Gemini CLI opencode Grok OpenAI API any MCP client

Questions

Does this work in Devin Desktop?+

Yes. Windsurf is now Devin Desktop and uses the same mcp_config.json format.

What does it cost?+

Connecting is free. You pay from your asms wallet: verification codes from $0.50, charged only when a code arrives and refunded automatically when none does, and rented numbers priced by country and period. Top up by card, PayPal or crypto.

Will Windsurf spend money without asking?+

Ordering a code and renting a number are marked as spending tools, so clients that support it ask for your approval first, and asms tells the agent to confirm the price with you before buying. Reading prices, balances and messages never spends anything.

What's the difference between a code and a rented number?+

A verification code order gives you a number for one code, for one service, and refunds itself if nothing arrives. A rented number is yours for a set period, from a day to a year, and receives every SMS sent to it: useful for testing your own app's SMS login or for an account you'll need to verify again later.

How do I disconnect it?+

Delete the API key in your asms dashboard, or remove asms under Connected apps if you signed in. Either one cuts off access straight away.

Give Windsurf a phone number

Create an account, top up from a few dollars, and connect. Codes from $0.50, refunded automatically when none arrives.

Create your account All agents