obul-x402engine-chain

name	obul-x402engine-chain
description	USE THIS SKILL WHEN: the user wants wallet balances, transactions, PnL, ENS resolution, token prices, or transaction simulation. Provides pay-per-use blockchain operations via x402engine through the Obul proxy.
homepage	https://x402engine.app
metadata	{"obul-skill":{"emoji":"⛓️","requires":{"env":[],"primaryEnv":""}}}
registries	{}

x402engine Chain

x402engine provides pay-per-call blockchain operations. Covers wallet analytics, ENS resolution, token metadata, and transaction simulation. No API key needed — payment is handled automatically via obulx.

Authentication

All requests use the obulx CLI, which handles x402 payment automatically.

Common Operations

Wallet Balances

Get token balances for a wallet address across supported chains.

Pricing: $0.005

Request:

obulx -X POST -H "Content-Type: application/json" \
  -d '{"address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045", "chain": "ethereum"}' \
  "https://x402-gateway-production.up.railway.app/api/wallet/balances"

Response: JSON with token balances, USD values, and total portfolio value.

Wallet Transactions

Get recent transaction history for a wallet address.

Pricing: $0.005

Request:

obulx -X POST -H "Content-Type: application/json" \
  -d '{"address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045", "chain": "ethereum"}' \
  "https://x402-gateway-production.up.railway.app/api/wallet/transactions"

Response: JSON array of recent transactions with hash, from, to, value, and timestamp.

Wallet PnL

Get profit and loss analysis for a wallet.

Pricing: $0.01

Request:

obulx -X POST -H "Content-Type: application/json" \
  -d '{"address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"}' \
  "https://x402-gateway-production.up.railway.app/api/wallet/pnl"

Response: JSON with realized/unrealized PnL breakdown per token.

ENS Resolve

Resolve an ENS name to an Ethereum address.

Pricing: $0.001

Request:

obulx "https://x402-gateway-production.up.railway.app/api/ens/resolve?name=vitalik.eth"

Response: JSON with the resolved Ethereum address.

ENS Reverse

Reverse resolve an Ethereum address to its ENS name.

Pricing: $0.001

Request:

obulx "https://x402-gateway-production.up.railway.app/api/ens/reverse?address=0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"

Response: JSON with the ENS name associated with the address.

Token Prices (Batch)

Get current prices for multiple tokens.

Pricing: $0.005

Request:

obulx -X POST -H "Content-Type: application/json" \
  -d '{"tokens": ["bitcoin", "ethereum", "solana"]}' \
  "https://x402-gateway-production.up.railway.app/api/token/prices"

Response: JSON with current prices for each requested token. Supports up to 200 tokens per request.

Token Metadata

• URL: https://x402-gateway-production.up.railway.app/api/token/metadata
• Method: GET
• Pricing: ~$0.002 per request

Request:

obulx "https://x402-gateway-production.up.railway.app/api/token/metadata?id=ethereum"

Response: JSON with token name, symbol, description, links, and contract addresses.

Crypto Price

• URL: https://x402-gateway-production.up.railway.app/api/crypto/price
• Method: GET
• Pricing: ~$0.001 per request

Request:

obulx "https://x402-gateway-production.up.railway.app/api/crypto/price?ids=bitcoin,ethereum"

Response: JSON with current USD prices for the requested coins.

Crypto Trending

• URL: https://x402-gateway-production.up.railway.app/api/crypto/trending
• Method: GET
• Pricing: ~$0.001 per request

Request:

obulx "https://x402-gateway-production.up.railway.app/api/crypto/trending"

Response: JSON array of currently trending cryptocurrencies.

Transaction Simulate

Simulate a transaction before sending to preview the outcome.

Pricing: $0.01

Request:

obulx -X POST -H "Content-Type: application/json" \
  -d '{"from": "0x...", "to": "0x...", "value": "1000000000000000000", "data": "0x...", "chain": "ethereum"}' \
  "https://x402-gateway-production.up.railway.app/api/tx/simulate"

Response: JSON with simulation results including gas estimate, state changes, and potential errors.

Endpoint Pricing Reference

Endpoint	Price	Purpose
POST /api/wallet/balances	$0.005	Get token balances for a wallet
POST /api/wallet/transactions	$0.005	Get transaction history
POST /api/wallet/pnl	$0.01	Get profit and loss analysis
GET /api/ens/resolve	$0.001	Resolve ENS name to address
GET /api/ens/reverse	$0.001	Reverse resolve address to ENS name
POST /api/token/prices	$0.005	Get batch token prices
GET /api/token/metadata	$0.002	Get token metadata
GET /api/crypto/price	$0.001	Get crypto prices
GET /api/crypto/trending	$0.001	Get trending cryptocurrencies
POST /api/tx/simulate	$0.01	Simulate a transaction

When to Use

• Wallet balances — User asks for a wallet's token balances or holdings
• Transaction history — User asks for a wallet's transaction history
• PnL analysis — User wants to check wallet PnL (profit and loss)
• ENS resolution — User wants to resolve an ENS name to an address (or reverse)
• Token prices — User asks for token prices or metadata
• Transaction simulation — User wants to simulate a transaction before sending
• Crypto prices — User asks about crypto prices, trending coins, or market search

Best Practices

• Supported chains — Wallet endpoints accept EVM addresses and support multiple chains (ethereum, base, polygon, arbitrum, etc.)
• ENS is Ethereum-specific — ENS endpoints work only with Ethereum
• Token limit — The token prices endpoint supports up to 200 tokens per request

Notes

• Prices range from $0.001 to $0.01 per request depending on endpoint complexity.
• Wallet endpoints accept EVM addresses and support multiple chains (ethereum, base, polygon, arbitrum, etc.).
• ENS endpoints are Ethereum-specific.
• The obulx CLI handles x402 payment automatically -- no USDC wallet or payment header needed.

Error Handling

Error	Cause	Solution
402 Payment Required	Payment not processed or insufficient	Verify your obulx setup is correct and your account has sufficient balance at my.obul.ai.
400 Bad Request	Invalid request body	Ensure required fields are present and correctly formatted.
404 Not Found	Address or token not found	Verify the wallet address or token symbol is correct.
429 Too Many Requests	Rate limit exceeded	Add a short delay between requests.
500 Internal Server Error	x402engine service issue	Wait a few seconds and retry. If persistent, the service may be experiencing downtime.