Current Bitcoin network fee rates and mempool backlog from mempool.space. Returns recommended fee rates in satoshis per virtual byte for target confirmation speeds (fastest ~next block, half-hour, hour, economy, minimum) plus the current mempool size (transaction count, total vsize, total fees waiting). Keyless, live. The BTC counterpart to crypto.gas-oracle (Ethereum) — fresh, fast-moving network state an agent cannot recall, for wallets, payment timing, and fee estimation.
/api/crypto/btc-feesPAYMENT-SIGNATURE.The btc fees API is a pay-per-call crypto endpoint built for AI agents and autonomous software. Current Bitcoin network fee rates and mempool backlog from mempool.space.
There is no signup and no API key. An agent (or any HTTP client) hits the endpoint, receives an x402 "402 Payment Required" challenge, signs a sub-cent USDC payment on Base or Solana, and retries — the data comes back on the paid request. That makes it a drop-in btc fees data source for an agent tool-use loop, an MCP host, or a backend that needs crypto data on demand without onboarding to yet another vendor portal.
# 1. Probe with no auth → 402 envelope with PaymentRequirements curl -sS 'https://2s.io/api/crypto/btc-fees' # 2. Sign + retry with PAYMENT-SIGNATURE: curl -sS 'https://2s.io/api/crypto/btc-fees' \ -H 'PAYMENT-SIGNATURE: <base64-json-payload>' # Or use the canonical runner (handles probe → sign → retry): # EVM_PRIVATE_KEY=0x... node --env-file=.env.local \ # --experimental-strip-types scripts/x402-pay.ts \ # 'https://2s.io/api/crypto/btc-fees'
import { TwoS } from '@2sio/sdk'
const client = new TwoS({
privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})
const result = await client.crypto.btcFees({})
console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)import os
from twosio import TwoS
client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])
result = client.crypto.btc_fees()
print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
// EVM_PRIVATE_KEY funds x402 payments per call.
// claude_desktop_config.json
{
"mcpServers": {
"2sio": {
"command": "npx",
"args": ["-y", "@2sio/mcp"],
"env": { "EVM_PRIVATE_KEY": "0x..." }
}
}
}
// 2. Once the server is running, agents call this tool via standard MCP:
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "crypto.btc-fees",
"arguments": {}
}
}| Field | Type | Description |
|---|---|---|
ok | boolean | one of: true |
items | array | |
total | integer | Total matching rows upstream; null when unknown. |
source | object |
{
"ok": true,
"items": [
{
"recommendedFeesSatPerVByte": {
"fastest": 1,
"halfHour": 1,
"hour": 1,
"economy": 1,
"minimum": 1
},
"mempool": {
"txCount": 1,
"vsizeBytes": 1,
"totalFeeSat": 1
},
"source": {
"provider": "example",
"url": "example",
"license": "example"
},
"note": "example"
}
],
"total": 1,
"source": {
"provider": "example",
"url": "example",
"license": "example"
}
}