---
title: Nostrbook Extension
description: Add Nostrbook MCP Server as a Goose Extension
---
import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';
This tutorial covers how to add the [Nostrbook MCP Server](https://gitlab.com/soapbox-pub/nostrbook) as a Goose extension to provide access to a comprehensive registry of Nostr documentation that helps users understand the decentralized social protocol, its implementation possibilities, and technical specifications.
:::tip TLDR
**Command**
```sh
npx -y xjsr @nostrbook/mcp
```
:::
## Configuration
:::info
Note that you'll need [Node.js](https://nodejs.org/) installed on your system to run this command, as it uses `npx`.
:::
1. [Launch the installer](goose://extension?cmd=npx&arg=-y&arg=%40nostrbook%2Fmcp&id=nostrbook&name=Nostrbook&description=A%20comprehensive%20registry%20of%20Nostr%20documentation%20with%20structured%20knowledge)
2. Press `Yes` to confirm the installation
3. Click `Save Configuration`
4. Scroll to the top and click `Exit` from the upper left corner
1. Run the `configure` command:
```sh
goose configure
```
2. Choose to add a `Command-line Extension`
```sh
┌ goose-configure
│
◇ What would you like to configure?
│ Add Extension
│
◆ What type of extension would you like to add?
│ ○ Built-in Extension
// highlight-start
│ ● Command-line Extension (Run a local command or script)
// highlight-end
│ ○ Remote Extension
└
```
3. Give your extension a name
```sh
┌ goose-configure
│
◇ What would you like to configure?
│ Add Extension
│
◇ What type of extension would you like to add?
│ Command-line Extension
│
// highlight-start
◆ What would you like to call this extension?
│ Nostrbook
// highlight-end
└
```
4. Enter the command
```sh
┌ goose-configure
│
◇ What would you like to configure?
│ Add Extension
│
◇ What type of extension would you like to add?
│ Command-line Extension
│
◇ What would you like to call this extension?
│ Nostrbook
│
// highlight-start
◆ What command should be run?
│ npx -y xjsr @nostrbook/mcp
// highlight-end
└
```
5. Enter the number of seconds Goose should wait for actions to complete before timing out. Default is 300s
```sh
┌ goose-configure
│
◇ What would you like to configure?
│ Add Extension
│
◇ What type of extension would you like to add?
│ Command-line Extension
│
◇ What would you like to call this extension?
│ Nostrbook
│
◇ What command should be run?
│ npx -y xjsr @nostrbook/mcp
│
// highlight-start
◆ Please set the timeout for this tool (in secs):
│ 300
// highlight-end
│
└
```
6. Choose to add a description. If you select "Yes" here, you will be prompted to enter a description for the extension.
```sh
┌ goose-configure
│
◇ What would you like to configure?
│ Add Extension
│
◇ What type of extension would you like to add?
│ Command-line Extension
│
◇ What would you like to call this extension?
│ Nostrbook
│
◇ What command should be run?
│ npx -y xjsr @nostrbook/mcp
│
◇ Please set the timeout for this tool (in secs):
│ 300
│
// highlight-start
◇ Would you like to add a description?
│ No
// highlight-end
│
└
```
7. Choose No when asked to add environment variables
```sh
┌ goose-configure
│
◇ What would you like to configure?
│ Add Extension
│
◇ What type of extension would you like to add?
│ Command-line Extension
│
◇ What would you like to call this extension?
│ Nostrbook
│
◇ What command should be run?
│ npx -y xjsr @nostrbook/mcp
│
◇ Please set the timeout for this tool (in secs):
│ 300
│
◇ Would you like to add a description?
│ No
│
// highlight-start
◆ Would you like to add environment variables?
│ No
│
// highlight-end
└ Added Nostrbook extension
```
## Example Usage
### Goose Prompt
> _Goose, what is the NIP-61 and how can I implement it?._
### Goose Output
Note that IDs have been changed to generic ones
:::note CLI
Tool Calls
─── read_nip | nostrbook ──────────────────────────
nip: 61
# NIP-61: Implementing Nutzaps
NIP-61 defines "Nutzaps," which are P2PK Cashu tokens where the payment itself acts as the receipt. This protocol allows for Bitcoin micropayments through the Nostr ecosystem using Cashu tokens.
## Core Concept
Nutzaps enable users to send small Bitcoin payments to each other through Nostr events, with the tokens being locked to the recipient's specified public key.
## Implementation Guide
### Prerequisites
1. Familiarize yourself with [Cashu](https://cashu.space/) and [P2PK token locking](https://github.com/cashubtc/nuts/blob/main/11.md)
2. Understand [NIP-60](https://github.com/nostr-protocol/nips/blob/master/60.md) for wallet functionality
3. Ensure your implementation supports NUT-11 (P2PK) and NUT-12 (DLEQ proofs)
### Step 1: Set Up Recipient Information (For Receiving Nutzaps)
Create and publish a `kind:10019` event to inform others how to send you money:
```json
{
"kind": 10019,
"tags": [
["relay", "wss://your-relay1.com"],
["relay", "wss://your-relay2.com"],
["mint", "https://your-trusted-mint.com", "sat"],
["pubkey", ""]
]
}
```
- The `pubkey` should be a dedicated public key (NOT your Nostr identity key)
- Store the corresponding private key safely in your NIP-60 wallet event
- List only mints you trust and monitor
### Step 2: Building the Sender Functionality
To implement nutzapping:
1. **Query recipient information**:
```javascript
// Fetch recipient's kind:10019 event
const recipientInfo = await relay.get({
kinds: [10019],
authors: [recipientPubkey]
});
```
2. **Extract mint and P2PK information**:
```javascript
const recipientMints = recipientInfo.tags
.filter(tag => tag[0] === 'mint')
.map(tag => tag[1]);
const recipientLockKey = recipientInfo.tags
.find(tag => tag[0] === 'pubkey')?.[1];
```
3. **Mint or swap tokens** at one of the recipient's trusted mints, P2PK-locking them to their specified key
4. **Publish the nutzap event**:
```json
{
"kind": 9321,
"content": "Thanks for your post!",
"tags": [
["proof", "{\"amount\":1,\"C\":\"02...3f\",\"id\":\"000...\",\"secret\":\"[\\\"P2PK\\\",...]\"}"],
["u", "https://recipient-specified-mint.com"],
["e", "", ""],
["p", ""]
]
}
```
### Step 3: Building the Recipient Functionality
To implement nutzap receiving:
1. **Query for incoming nutzaps**:
```javascript
// Subscribe to nutzap events
relay.subscribe([
{
kinds: [9321],
"#p": [myPubkey],
"#u": myTrustedMints,
since: lastCheckTimestamp
}
]);
```
2. **Validate incoming nutzaps**:
- Verify the token is from a mint you've specified
- Verify the token is locked to your P2PK key
- Verify the DLEQ proof
3. **Redeem the token**:
- Swap the P2PK token into your wallet
- Create a `kind:7376` event to record redemption:
```json
{
"kind": 7376,
"content": "",
"tags": [
["e", "", "", "redeemed"],
["p", ""]
]
}
```
### Important Implementation Details
1. **P2PK Key Prefixing**: Always prefix the P2PK-lock public key with "02" for compatibility
2. **Token Verification**: Implement local verification of DLEQ proofs
3. **Mint URL Normalization**: Normalize mint URLs to avoid issues with slight URL variations
4. **User Guidance**: Guide users to use only NUT-11 and NUT-12 compatible mints
5. **Publishing Locations**: Publish nutzap events to the recipient's specified relays
## Testing
When testing your implementation:
1. Create test nutzaps with small amounts
2. Verify token redemption works correctly
3. Check that redemption records are properly created
4. Test with multiple mints for compatibility
## Security Considerations
- Never use the user's main Nostr key for P2PK operations
- Ensure proper encryption of sensitive wallet data
- Validate all proofs before attempting to redeem tokens
- Only interact with explicitly trusted mints
By following these steps, you can implement a complete nutzap solution that allows users to send and receive Bitcoin micropayments through the Nostr protocol using Cashu tokens.
:::