Overview

What You Need Before Starting

To use the Passkallet BaaS API, you need three things:

1. A Passkallet account -- Sign up at passkallet.com
2. An organization -- This is your workspace where API keys and wallets live
3. An API key -- This is how the API knows who you are

That is it. No blockchain node, no Metamask, no Solidity knowledge. Just an API key and fetch().

Base URL

Every single API call goes to this base URL:

https://gateway.dev.passkallet.com/sepolia/api/v1/passkallet/baas

For example, to list wallets, you call:

GET https://gateway.dev.passkallet.com/sepolia/api/v1/passkallet/baas/wallets

Authentication

Every request must include your API key in the x-api-key header.

curl https://gateway.dev.passkallet.com/sepolia/api/v1/passkallet/baas/wallets \
  -H "x-api-key: pk_live_abc123xyz"

In JavaScript:

const response = await fetch(
  "https://gateway.dev.passkallet.com/sepolia/api/v1/passkallet/baas/wallets",
  {
    headers: {
      "x-api-key": "pk_live_abc123xyz",
    },
  }
);
const data = await response.json();

Response Format

All responses follow this consistent structure:

Successful response:

{
  "statusCode": 200,
  "content": {
    // your data here
  }
}

Error response:

{
  "statusCode": 400,
  "content": {
    "message": "rpIdHash does not match any registered domain for this organization"
  }
}

The statusCode field always matches the HTTP status code. The content field holds your data on success. On errors, content.message explains what went wrong.

Step-by-Step Setup

Here is the full flow from zero to your first API call:

Total time: about 5 minutes.

What Happens Under the Hood

When you call our API to, say, create a wallet:

1. Your server sends a POST request with the x-api-key header
2. Passkallet validates your API key and checks permissions (scopes)
3. Passkallet deploys a smart contract wallet on the Polygon network
4. Passkallet sends the wallet address and transaction hash back to you
5. Your server stores the address and shows it to your user

You never need to worry about:

• Gas fees (Passkallet pays them through account abstraction)
• Private keys (Passkeys replace traditional private keys)
• Nonce management (Passkallet handles transaction ordering)
• RPC nodes (You talk to our API, not to blockchain nodes)