Building a Paid AI Agent with OpenClaw and Nevermined

The Nevermined OpenClaw plugin lets you monetize AI agents directly from chat channels. Subscribers pay per-request using the x402 payment protocol, and builders collect revenue automatically through on-chain payment plans. This guide walks through building a Weather Oracle — a paid agent that serves weather forecasts and charges 1 credit per request.

What You Get

The plugin adds 9 payment tools and 2 slash commands to your OpenClaw gateway: Subscriber tools — for users who consume paid services:

Tool	Purpose
`nevermined_checkBalance`	Check remaining credits on a plan
`nevermined_getAccessToken`	Get an x402 token for authenticating requests (crypto or fiat)
`nevermined_orderPlan`	Purchase a crypto payment plan
`nevermined_orderFiatPlan`	Purchase a fiat payment plan (returns Stripe checkout URL)
`nevermined_listPaymentMethods`	List enrolled credit cards for fiat payments
`nevermined_queryAgent`	Send a paid query to an agent (crypto or fiat)

Builder tools — for developers who create paid services:

Tool	Purpose
`nevermined_registerAgent`	Register an agent with a payment plan (crypto or fiat)
`nevermined_createPlan`	Create a standalone payment plan
`nevermined_listPlans`	List your payment plans

Slash commands: /nvm_login and /nvm_logout for authentication. Paid HTTP endpoint: An x402-compatible endpoint on the gateway that handles payment verification, request processing, and credit settlement automatically.

Prerequisites

An OpenClaw gateway instance (v2026.2+)
Node.js >= 18
A Nevermined account with an API key

Step 1: Install the Plugin

From your OpenClaw gateway server:

openclaw plugin install @nevermined-io/openclaw-plugin

Or install manually by placing the package in ~/.openclaw/extensions/nevermined/. After installation, restart the gateway:

openclaw gateway restart

You should see in the logs:

Registered 9 Nevermined payment tools

Step 2: Authenticate

Send /nvm_login from any connected chat channel (Telegram, Discord, etc.). The plugin supports two flows: Browser login (if your server has a display):

/nvm_login

A browser window opens for Nevermined authentication. The API key is captured automatically. Manual login (headless servers):

/nvm_login sandbox:eyJhbGciOiJFUzI1NksifQ...

Paste your API key directly. Get one from Nevermined App under Settings > API Keys. Use sandbox for testing, live for production.

Step 3: Register Your Agent and Payment Plan

Ask your Claw to register an agent. In any chat channel, send a message like:

Register a Nevermined agent called “Weather Oracle” at URL https://my-gateway.example.com/nevermined/agent with a plan named “Weather Forecast” priced at 1000000 (1 USDC) to address 0xYourWalletAddress with token 0x036CbD53842c5426634e7929541eC2318f3dCF7e granting 5 credits.

The agent will call nevermined_registerAgent with these parameters:

Parameter	Value	Description
`name`	Weather Oracle	Display name on Nevermined
`agentUrl`	`https://my-gateway.example.com/nevermined/agent`	Public URL of your paid endpoint
`planName`	Weather Forecast	Name for the payment plan
`priceAmounts`	`1000000`	Price in token units (1 USDC = 1,000,000 wei)
`priceReceivers`	`0xYourWalletAddress`	Your wallet that receives payments
`creditsAmount`	`5`	Credits granted per purchase
`tokenAddress`	`0x036CbD53842c5426634e7929541eC2318f3dCF7e`	USDC on Base Sepolia. Omit for native token.

The tool returns the agentId and planId — save these for the next step.

Step 4: Enable the Paid Endpoint

Add the returned IDs and enable the paid endpoint in your gateway config (~/.openclaw/openclaw.json):

{
  "plugins": {
    "entries": {
      "openclaw-plugin": {
        "enabled": true,
        "config": {
          "nvmApiKey": "sandbox:eyJhbG...",
          "environment": "sandbox",
          "planId": "<your-plan-id>",
          "agentId": "<your-agent-id>",
          "enablePaidEndpoint": true,
          "agentEndpointPath": "/nevermined/agent",
          "creditsPerRequest": 1
        }
      }
    }
  }
}

Restart the gateway. You should see:

Registered 9 Nevermined payment tools
Registered paid endpoint at /nevermined/agent

The paid endpoint handles the full x402 lifecycle:

Extracts the payment-signature header from incoming requests
Calls verifyPermissions to check the subscriber has credits
Processes the request (runs your agent handler)
Calls settlePermissions to burn credits
Returns the response with a payment-response header

Configuration Reference

Field	Required	Default	Description
`nvmApiKey`	No	—	API key (set via `/nvm_login` or config)
`environment`	No	`sandbox`	`sandbox` for testing, `live` for production
`planId`	No	—	Default plan ID for tools and the paid endpoint
`agentId`	No	—	Default agent ID
`creditsPerRequest`	No	`1`	Credits burned per request
`enablePaidEndpoint`	No	`false`	Enable the x402 paid HTTP endpoint
`agentEndpointPath`	No	`/nevermined/agent`	Path for the paid endpoint

Step 5: Test as a Subscriber

From the same gateway (or a different one with a subscriber API key), test the full flow:

Order the plan

Order the Weather Oracle plan <plan-id>

The Claw calls nevermined_orderPlan. You receive 5 credits.

Check your balance

Check my Nevermined balance for plan <plan-id>

Should show 5 credits.

Query the agent

Ask the Weather Oracle at http://localhost:18789/nevermined/agent about the weather in Barcelona

The Claw calls nevermined_queryAgent, which:

Acquires an x402 access token
Sends the prompt with a PAYMENT-SIGNATURE header
The paid endpoint verifies, processes, and settles
Returns the weather forecast

Verify credit burn

Check my balance again

Should show 4 credits — one was consumed.

Fiat Payments (Credit Card)

The plugin supports fiat payments via credit card delegation, allowing users who have enrolled a card through the Nevermined App to pay for agent queries without cryptocurrency.

1. Enroll a card

Users enroll a credit card via the Nevermined App under Settings > Payment Methods.

2. List enrolled cards

List my payment methods

The Claw calls nevermined_listPaymentMethods and returns the enrolled cards with brand, last 4 digits, and expiration.

3. Order a fiat plan

Order the fiat plan <plan-id>

The Claw calls nevermined_orderFiatPlan, which returns a Stripe checkout URL. The user completes payment in a browser.

4. Query an agent with fiat

Ask the Weather Oracle at http://localhost:18789/nevermined/agent about the weather in Paris, pay with my credit card

The Claw calls nevermined_queryAgent with paymentType: fiat. The plugin:

Looks up enrolled payment methods (or uses the specified paymentMethodId)
Gets an x402 access token using the nvm:card-delegation scheme
Sends the request with the PAYMENT-SIGNATURE header
The agent verifies and settles as usual

You can also set paymentType: fiat in the plugin config to make fiat the default for all calls.

Custom Agent Handlers

The plugin includes a mock weather handler for demonstration. To use your own logic, pass a custom agentHandler when registering the plugin:

import neverminedPlugin from '@nevermined-io/openclaw-plugin'

neverminedPlugin.register(api, {
  agentHandler: async (body) => {
    const response = await myAIModel.generate(body.prompt)
    return { result: response }
  },
})

The handler receives { prompt: string } and returns any JSON-serializable object.

Credit Balance Awareness

When the plugin is authenticated and a planId is configured, it automatically injects the current credit balance into the agent’s context before each prompt. This means your Claw can proactively warn users when credits are running low:

“You have 2 credits remaining on the Weather Forecast plan. Consider ordering more credits.”

The balance is cached for 60 seconds to avoid excessive API calls.

How It Works

The plugin implements the x402 payment protocol for agent-to-agent payments. It supports two payment schemes:

Crypto (nvm:erc4337) — on-chain payments using session keys and smart accounts
Fiat (nvm:card-delegation) — credit card payments via Stripe delegation

Both schemes follow the same token flow:

Subscriber Claw                    Builder Claw (Gateway)
      │                                     │
      │  1. getX402AccessToken(planId,       │
      │     tokenOptions)                    │
      │─────────────────────────────────────>│  Nevermined API
      │<─────────────────────────────────────│  returns token
      │                                     │
      │  2. POST /nevermined/agent           │
      │     Header: payment-signature: token │
      │     Body: { prompt: "..." }          │
      │─────────────────────────────────────>│
      │                                     │  3. verifyPermissions()
      │                                     │  4. Process request
      │                                     │  5. settlePermissions()
      │  6. Response + payment-response hdr  │
      │<─────────────────────────────────────│

For crypto, credits are managed on-chain through the Nevermined Protocol. For fiat, credits are charged against the delegated card via Stripe. In both cases, verifyPermissions checks the subscriber’s balance without consuming credits, and settlePermissions consumes them only after successful processing.

Next Steps

Commands Reference — full parameter documentation for all tools
Setup Reference — detailed configuration options
Nevermined Docs — platform documentation
x402 Protocol — payment protocol specification
OpenClaw Plugin Development — building OpenClaw plugins

TypeScript SDK

Python SDK

CLI

OpenClaw Plugin

Building a Paid AI Agent with OpenClaw and Nevermined

Building a Paid AI Agent with OpenClaw and Nevermined

What You Get

Prerequisites

Step 1: Install the Plugin

Step 2: Authenticate

Step 3: Register Your Agent and Payment Plan

Step 4: Enable the Paid Endpoint

Configuration Reference

Step 5: Test as a Subscriber

Order the plan

Check your balance

Query the agent

Verify credit burn

Fiat Payments (Credit Card)

1. Enroll a card

2. List enrolled cards

3. Order a fiat plan

4. Query an agent with fiat

Custom Agent Handlers

Credit Balance Awareness

How It Works

Next Steps

TypeScript SDK

Python SDK

CLI

OpenClaw Plugin

Documentation Index

​Building a Paid AI Agent with OpenClaw and Nevermined

​What You Get

​Prerequisites

​Step 1: Install the Plugin

​Step 2: Authenticate

​Step 3: Register Your Agent and Payment Plan

​Step 4: Enable the Paid Endpoint

​Configuration Reference

​Step 5: Test as a Subscriber

​Order the plan

​Check your balance

​Query the agent

​Verify credit burn

​Fiat Payments (Credit Card)

​1. Enroll a card

​2. List enrolled cards

​3. Order a fiat plan

​4. Query an agent with fiat

​Custom Agent Handlers

​Credit Balance Awareness

​How It Works

​Next Steps

Building a Paid AI Agent with OpenClaw and Nevermined

What You Get

Prerequisites

Step 1: Install the Plugin

Step 2: Authenticate

Step 3: Register Your Agent and Payment Plan

Step 4: Enable the Paid Endpoint

Configuration Reference

Step 5: Test as a Subscriber

Order the plan

Check your balance

Query the agent

Verify credit burn

Fiat Payments (Credit Card)

1. Enroll a card

2. List enrolled cards

3. Order a fiat plan

4. Query an agent with fiat

Custom Agent Handlers

Credit Balance Awareness

How It Works

Next Steps