← The evidence ledger
Evidence row 4452
Observed , by baseline/1.
- Kind
- listing
- About
- source_record agentic_market:x402-echo-service-onrender-com
- Recorded
- Previous row
- None: the first of its kind about this subject
- Body SHA-256
- 0ed4932eb6c331ba616b55213657827444effe05f0296aa85655b1cae2dab46e
- Leaf
- 0x6fb81bc275b32f297917cbbe7e22fa624205d20859c9f1e7620aed2c72120524
What was observed
{
"endpoints": [
[
"x402",
"https://x402-echo-service.onrender.com/base64"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/block"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/code"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/erc20-balance"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/eth-balance"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/gas"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/nonce"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/token"
],
[
"x402",
"https://x402-echo-service.onrender.com/chain/tx"
],
[
"x402",
"https://x402-echo-service.onrender.com/echo"
],
[
"x402",
"https://x402-echo-service.onrender.com/hash"
],
[
"x402",
"https://x402-echo-service.onrender.com/time"
],
[
"x402",
"https://x402-echo-service.onrender.com/uuid"
],
[
"x402",
"https://x402-echo-service.onrender.com/web/search"
]
],
"name": "x402-echo-service.onrender.com",
"owner_address": null,
"raw": {
"caip2_networks": [
"eip155:8453"
],
"category": "",
"description": "",
"domain": "x402-echo-service.onrender.com",
"endpoints": [
{
"description": "Encode or decode base64. POST {\"mode\":\"encode\",\"input\":\"...\"} or {\"mode\":\"decode\",...}. Supports standard and url-safe alphabets via {\"urlsafe\":true}. Decoding validates the input and reports an error rather than returning silent garbage.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "hello world",
"group": "body",
"name": "input",
"required": false,
"type": "string"
},
{
"default": null,
"description": "",
"enumValues": [],
"example": "encode",
"group": "body",
"name": "mode",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "2",
"l30DaysUniquePayers": "2"
},
"serviceName": "Base64 Codec",
"tags": [
"base64",
"encode",
"decode",
"codec",
"utility"
],
"url": "https://x402-echo-service.onrender.com/base64"
},
{
"description": "Read the head of the Base chain, or a specific block. POST {} for the latest block, or {\"number\":12345678} for one by height. Returns number, hash, unix timestamp, gas used and transaction count. Useful as an authoritative chain clock.",
"method": "POST",
"parameters": [],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "Base Block",
"tags": [
"block",
"base",
"onchain",
"chain-head",
"rpc"
],
"url": "https://x402-echo-service.onrender.com/chain/block"
},
{
"description": "Determine whether an address on Base is a contract or an externally owned account. POST {\"address\":\"0x...\"} and receive isContract, the bytecode size in bytes and its keccak-256 hash. Useful before sending funds to an unfamiliar address.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"group": "body",
"name": "address",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "Contract Check",
"tags": [
"contract",
"bytecode",
"base",
"onchain",
"eoa"
],
"url": "https://x402-echo-service.onrender.com/chain/code"
},
{
"description": "Read an ERC-20 token balance on Base. POST {\"address\":\"0x...\",\"token\":\"0x...\"} and receive the raw balance, the token decimals and the human-readable amount. Defaults to USDC when token is omitted. Live chain state, no indexer lag.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "0x9Cc774A8eD49d89cBA1A288F4a050B8F7FbA77EE",
"group": "body",
"name": "address",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "ERC-20 Balance",
"tags": [
"erc20",
"balance",
"base",
"onchain",
"token"
],
"url": "https://x402-echo-service.onrender.com/chain/erc20-balance"
},
{
"description": "Read the native ETH balance of an address on Base. POST {\"address\":\"0x...\"} and receive the balance in wei and in ether. Live chain state read directly from a node, with no indexer lag and no API key.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "0x9Cc774A8eD49d89cBA1A288F4a050B8F7FbA77EE",
"group": "body",
"name": "address",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "Native Balance",
"tags": [
"eth",
"balance",
"base",
"onchain",
"native"
],
"url": "https://x402-echo-service.onrender.com/chain/eth-balance"
},
{
"description": "Current gas conditions on Base. POST {} and receive the legacy gas price and the EIP-1559 base fee of the latest block, in wei and gwei. Useful for agents deciding whether to transact now or wait.",
"method": "POST",
"parameters": [],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "3",
"l30DaysUniquePayers": "3"
},
"serviceName": "Gas Price",
"tags": [
"gas",
"fees",
"base",
"eip1559",
"onchain"
],
"url": "https://x402-echo-service.onrender.com/chain/gas"
},
{
"description": "Read the transaction count of an address on Base. POST {\"address\":\"0x...\"} with an optional {\"pending\":true} to include the mempool. Returns the nonce an agent should use for its next transaction.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "0x9Cc774A8eD49d89cBA1A288F4a050B8F7FbA77EE",
"group": "body",
"name": "address",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "Account Nonce",
"tags": [
"nonce",
"transaction-count",
"base",
"onchain",
"account"
],
"url": "https://x402-echo-service.onrender.com/chain/nonce"
},
{
"description": "Read ERC-20 metadata on Base. POST {\"token\":\"0x...\"} and receive the name, symbol, decimals and total supply, with the supply given both raw and decimal-adjusted. Reports a clear error when the address is not a token contract.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"group": "body",
"name": "token",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "Token Metadata",
"tags": [
"token",
"erc20",
"metadata",
"base",
"supply"
],
"url": "https://x402-echo-service.onrender.com/chain/token"
},
{
"description": "Look up a transaction on Base by hash. POST {\"hash\":\"0x...\"} and receive its status, block number, from and to addresses, value, gas used and effective gas price. Returns a clear not-found rather than an empty object when the hash is unknown.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "0x962895f4b604ce745b6cd76e588d62fcf4fb59f9d6e67d0a17a7769f6ab15e4e",
"group": "body",
"name": "hash",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "1",
"l30DaysUniquePayers": "1"
},
"serviceName": "Transaction Lookup",
"tags": [
"transaction",
"receipt",
"base",
"onchain",
"lookup"
],
"url": "https://x402-echo-service.onrender.com/chain/tx"
},
{
"description": "Echo service for x402 protocol research. POST a JSON body with a \"message\" string; the response returns the message, its SHA-256 digest and a server timestamp. Payment is live: $0.001 USDC on Base is verified and settled via the Coinbase CDP facilitator, so callers ARE charged. The response is computed before settlement, and the settlement tx hash is returned in the body and in PAYMENT-RESPONSE.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": "hello world",
"group": "body",
"name": "message",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": null,
"serviceName": "x402 research echo",
"tags": [
"x402",
"echo",
"protocol-conformance",
"security-research",
"agents"
],
"url": "https://x402-echo-service.onrender.com/echo"
},
{
"description": "Compute cryptographic digests of a string. POST {\"input\":\"...\",\"algorithms\":[\"sha256\"]} and receive one hex digest per requested algorithm. Supports sha256, sha512 and keccak256. Deterministic, no storage, no upstream calls.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": [],
"group": "body",
"name": "algorithms",
"required": false,
"type": "array"
},
{
"default": null,
"description": "",
"enumValues": [],
"example": "hello world",
"group": "body",
"name": "input",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "2",
"l30DaysUniquePayers": "2"
},
"serviceName": "Hash Digest",
"tags": [
"hash",
"sha256",
"keccak",
"digest",
"utility"
],
"url": "https://x402-echo-service.onrender.com/hash"
},
{
"description": "Server time in several formats at once. POST {} and receive the current UTC instant as ISO-8601, unix seconds, unix milliseconds and RFC-2822. Useful for agents that need an authoritative clock they did not compute themselves.",
"method": "POST",
"parameters": [],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "2",
"l30DaysUniquePayers": "2"
},
"serviceName": "Time Formats",
"tags": [
"time",
"timestamp",
"clock",
"iso8601",
"utility"
],
"url": "https://x402-echo-service.onrender.com/time"
},
{
"description": "Generate cryptographically random UUIDv4 identifiers. POST {\"count\":10} and receive that many unique v4 UUIDs, 1 to 100 per call. Uses the platform CSPRNG. No storage.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": 3,
"group": "body",
"name": "count",
"required": false,
"type": "number"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": {
"l30DaysTotalCalls": "13",
"l30DaysUniquePayers": "6"
},
"serviceName": "UUID Generator",
"tags": [
"uuid",
"identifier",
"random",
"generator",
"utility"
],
"url": "https://x402-echo-service.onrender.com/uuid"
},
{
"description": "Web search for agents. POST a JSON body with a \"query\" string and an optional \"limit\" (1-20); returns ranked results, each with a title, url and text snippet. Keyword and semantic matching, no API key required, billed per call: $0.001000 USDC.",
"method": "POST",
"parameters": [
{
"default": null,
"description": "",
"enumValues": [],
"example": 5,
"group": "body",
"name": "limit",
"required": false,
"type": "number"
},
{
"default": null,
"description": "",
"enumValues": [],
"example": "x402 protocol",
"group": "body",
"name": "query",
"required": false,
"type": "string"
}
],
"pricing": {
"amount": "0.001",
"currency": "USDC",
"maxAmount": "",
"minAmount": "",
"network": "eip155:8453",
"scheme": "exact"
},
"providerName": "",
"quality": null,
"serviceName": "Open Web Search",
"tags": [
"web-search",
"search",
"agents",
"research",
"retrieval"
],
"url": "https://x402-echo-service.onrender.com/web/search"
}
],
"enriched": false,
"iconUrl": "https://res.cloudinary.com/bdb-prod/image/upload/c_fill,ar_1:1,w_256,h_256,f_auto,q_auto/v1787754105/bazaar-icons/222b7a4262b684da.png",
"id": "x402-echo-service-onrender-com",
"integrationType": "",
"isNew": false,
"name": "x402-echo-service.onrender.com",
"networks": [
"Base"
],
"priceSummary": {
"avgCostBasis": "exact",
"avgCostPerTransaction": "0.001",
"currency": "USDC",
"maxAmount": "0.001",
"minAmount": "0.001"
},
"provider": "x402-echo-service.onrender.com",
"providerUrl": "",
"serviceName": "",
"tags": [
"base64",
"encode",
"decode",
"codec",
"utility",
"block",
"base",
"onchain",
"chain-head",
"rpc",
"contract",
"bytecode",
"eoa",
"erc20",
"balance",
"token",
"eth",
"native",
"gas",
"fees",
"eip1559",
"nonce",
"transaction-count",
"account",
"metadata",
"supply",
"transaction",
"receipt",
"lookup",
"x402",
"echo",
"protocol-conformance",
"security-research",
"agents",
"hash",
"sha256",
"keccak",
"digest",
"time",
"timestamp",
"clock",
"iso8601",
"uuid",
"identifier",
"random",
"generator",
"web-search",
"search",
"research",
"retrieval"
]
},
"source": "agentic_market",
"summary": ""
}What the leaf hashes
{"body":"0ed4932eb6c331ba616b55213657827444effe05f0296aa85655b1cae2dab46e","id":4452,"kind":"listing","method":"baseline/1","observed_us":1793025277907825,"prev":null,"subject":"agentic_market:x402-echo-service-onrender-com","subject_kind":"source_record"}Proof
Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of (296695 rows).
- 0x6fb8173190a11d382d4d077dc81c0a183aff8a95b6835695245b565e16c57c3c
- 0xd0e353444eebb30ab968050fe46bca8fb2157accb29a23cc80b5601a82e3b9a6
- 0x8345fd29e060d8e91e434d70157c72cff0e2778b4515ec51967dd0a48d3e52cc
- 0x397c1e8d9d9e16b0904819489842b4edaad427bda45b7293ba3c014106012a69
- 0x8653d02bfcfdf4285b9376072dfb09c3708072cf810959df669206307567f7a5
- 0x3b335c873ce6c12294f8464bc3f8f07eef92ebb11c5855ff4b48a13b46cbf72b
- 0x500ad9ef96f1a834b26b7909bb144b7ab133ed1d82463e92c92a7c270a8e5b76
- 0x94ea7128cd74754f1cb34c8ac8c65ef49512d765cfa5f29d6251404418c38e36
- 0x5099e35a57aa80fd117292846407c0cd1a0db62ac59ff4e37ca31369444c7b45
- 0xc70d346129c156fcaba34294b762967bcbb4de7a74526ae0ff9df5eeef4e6d37
- 0x83da3d3b0ffc00454b09f0b6f54a0a4bb8b5fabd87854d6bb2d7abda681b5d72
- 0x5be1d69fd9353c3a75685caffea8c98e8f079f5072011c82517cc5f365ba32f8
- 0x14b83e3bc6587240f31cd033d09d131e0775b7b00aada9042597008a70399013
- 0xfc9b5a81a7a83a1c735a4fe64590beb9db14d2366f463161358af28c3ea9a81d
- 0xa2d436d488e3600b0e5c3e3ed9c9234cd52853c59830b786334fd0c4292d9f40
- 0x47b89901b0f07938a6b9a66ddf35683903f79d756a7c7763665fd632758b08d0
- 0x9a83be955a206deb65b995adfd92c58fa31c95fbbf926bd199d300e70b08b26d
- 0x20704208aa6923d6b2450ef74ede87a6e0265d46447926038fe9506e9e154b2d
- 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a
- Day root
- 0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8
- Chained
- 0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a
- Published
- On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae