Crypto Address Activity API

WATCHER: get a signed callback the moment a crypto address transacts.

Overview

WATCHER: get a signed callback the moment a crypto address transacts. Arm once, pay once (no account, no API key) — we watch Base, Ethereum, or Bitcoin and POST your custom payload to callbackUrl when the address sends/receives native coins, ERC-20s, or ERC-721s. Filter by direction (in/out/both), asset type, and a USD minimum (minValueUsd) to skip dust. Bounded by a 30-day / 25-fire window. Deliveries are EIP-191-signed by our published key (verify offline) and retried with exponential backoff; missed pushes are recoverable via watchers.status. Returns a watcherId.

Endpoint

Method	Endpoint	Price	Description
POST	/v1/marketplace/api/crypto-address-activity	$0.14375	Invoke Crypto Address Activity (Blockchain) and return the upstream response.

How to call it

Requests are paid per call over the x402 protocol. Call the endpoint, receive a 402 Payment Required quote, then repeat the request with the signed payment header. The SDKs do both steps for you.

# 1. Ask for a quote
curl -i -X POST https://jarvisclaw.ai/v1/marketplace/api/crypto-address-activity \
  -H 'Content-Type: application/json' \
  -d '{}'

# 2. Pay it (the SDK signs and retries for you)
curl -X POST https://jarvisclaw.ai/v1/marketplace/api/crypto-address-activity \
  -H 'Content-Type: application/json' \
  -H 'X-PAYMENT: <signed-payload>' \
  -d '{}'

Parameters

Taken from the request example this API publishes.

Name	In	Type	Example
address	body	string	"xxxxxxxxxxxxxxxxxxxx"
assetTypes	body	array	["native"]
callbackUrl	body	string	"https://example.com"
chain	body	string	"base"
direction	body	string	"in"
expiresInSeconds	body	number	60
label	body	string	"example"
maxFires	body	number	1
minValueUsd	body	number	0
payload	body	object	{}

Example response

{
  "data": {
    "ok": true,
    "items": [
      {
        "watcherId": "example",
        "status": "example",
        "chain": "example",
        "address": "example",
        "direction": "example",
        "assetTypes": [
          "example"
        ],
        "minValueUsd": 1,
        "maxFires": 1,
        "firesRemaining": 1,
        "expiresAt": "example",
        "statusUrl": "example",
        "callbackSigner": "example"
      }
    ],
    "total": 1,
    "source": {
      "provider": "example",
      "url": "example",
      "license": "example"
    }
  },
  "meta": {
    "endpoint": "watchers.crypto-address-activity",
    "version": null,
    "caller": "x402",
    "cost": {
      "usd": 0.125
    },
    "settlement": {
      "txHash": "[redacted]",
      "network": "eip155:8453",
      "success": true
    }
  }
}

FAQ

How much does the Crypto Address Activity API cost?

$0.14375 USDC per call, paid per call over x402. There is no subscription, minimum or monthly fee.

Do I need an API key?

No. Call the endpoint, read the 402 Payment Required quote, and repeat the request with a signed USDC payment header. An account API key also works if you prefer prepaid billing.

Which chains can I pay on?

USDC on Base or on Solana. The 402 quote lists the accepted networks and the exact amount; the JarvisClaw SDKs sign and retry for you.

How do I call it from an AI agent?

Send POST to the endpoint above from any HTTP client, or connect the JarvisClaw MCP server and let the agent find and call it with the search_apis and get_api_detail tools.

Related APIs

• Crypto Markets
• Crypto News Api
• Btc Fees
• Address Screen
• Defi Analytics

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