Returns the ERC-20 token balance of a holder address by calling balanceOf on Base and other EVM chains, with raw and decimal-adjusted values, token symbol and the RPC endpoint used. Responses carry an Ed25519 signed receipt. Three free calls per wallet via the X-WALLET header.
Pay from $0.001 per request in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.
ASSESSMENT
updated 5h agoEvidence-backed signals, not a single score. Click any chip for the proof. Measured values stay read-only; unknown is honest.
reliability 83.7%
- uptime 24h
- 86.7%
- uptime 7d
- 83.7%
- uptime 30d
- 83.7%
- uptime 90d
- 83.7%
- response p95
- 8450ms
- avg response
- 2191ms
- total checks
- 47
compliance A (11/11)
11 of 11 x402 conformance checks pass. Full checklist below.
price $0.001 (p29 in Blockchain)
- price (min)
- $0.001
- category percentile (min)
- p29 in Blockchain
- endpoints / prices
- 1 / 1
- model
- flat
- stability
- 100%
risk clean
No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.
traction $0.03 30d · 0 buyers
- volume 30d
- $0.03
- buyers 30d
- 0
- settlements 30d
- 3
- last settlement
- 2026-07-21
- top buyer share
- 48% of 30d volume
- trend 7d vs 30d
- 0.12x the 30d daily rate
- networks
- eip155:8453
Attributed pro-quota: this payout address is shared, so volume and buyers are the operator-level figure divided by the services sharing it. A declared convention, not an individually observed measure, and still a conservative undercount.
Top buyer share is a concentration signal, not part of the ranking score.
WHAT IT DOES
ai-derivedProvides ERC-20 token balance information for wallet addresses via the balanceOf method.
- category
- blockchain-token-balance
- in
- body
- auth
- api key
AI-generated summary. The measured data is never altered by it.
ENDPOINTS
| METHOD | PATH | DESCRIPTION | PRICE | NETWORK | ASSET |
|---|---|---|---|---|---|
| POST | /service | ERC-20 token balance for a holder via balanceOf. Deterministic, Ed25519-signed. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure. $0.003 USDC via x402 on Base. SYNTHORA. | $0.001 | Base | USDC |
REQUEST / RESPONSE EXAMPLE
An unpaid request to POST /service returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.
curl -i -X POST 'https://rpc-erc20-balance.hergertsynthora.com/service'
// 402 response (captured by monitor) · 1 payload · click to expand
[
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x10800a5a5B9d72251566EC651E862A8b4B427dE0",
"amount": "1000",
"scheme": "exact",
"network": "eip155:8453",
"mimeType": "application/json",
"resource": "https://rpc-erc20-balance.hergertsynthora.com/service",
"description": "ERC-20 token balance for a holder via balanceOf. Deterministic, Ed25519-signed. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure. $0.003 USDC via x402 on Base. SYNTHORA.",
"maxAmountRequired": "1000",
"maxTimeoutSeconds": 300
}
],
"freeTier": {
"note": "send header X-WALLET: 0x<your Base address> for a free trial",
"header": "X-WALLET",
"callsPerWallet": 3
},
"resource": {
"url": "https://rpc-erc20-balance.hergertsynthora.com/service",
"mimeType": "application/json",
"description": "ERC-20 token balance for a holder via balanceOf. Deterministic, Ed25519-signed. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure. $0.003 USDC via x402 on Base. SYNTHORA."
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"chain": "base",
"token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"address": "0x28C6c06298d514Db089934071355E5743bf21d60"
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"ok": true,
"niche": "rpc-erc20-balance",
"result": {
"op": "erc20-balance"
}
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"required": [
"address",
"token"
],
"properties": {
"chain": {
"type": "string",
"description": "chain"
},
"token": {
"type": "string",
"description": "token"
},
"address": {
"type": "string",
"description": "address"
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"ok": {
"type": "boolean"
},
"type": "object",
"niche": {
"type": "string"
}
}
}
}
}
}
}
},
"x402Version": 2
}
] UPTIME
RECENT CHECKS
OVER TIME
All charts share the 7d window selected here. Every series is also served as JSON at /api/v1/services/synthora-erc-20-token-balance/price, /scores, /volume and /buyers. On-chain volume and distinct buyers are measured over the service's settlement address and are a conservative undercount (only settlements that reach a measured facilitator are counted).
Shared payout address (61 other services). These bars are the full shared address (operator-level), so do not sum them across the services that share it. Where a per-service figure is attributed, the assessment block and the ranking, it is the address total divided pro-quota by the 62 services sharing it: a declared convention, not an individually observed measure.
Shared payout address (61 other services). These bars are the full shared address (operator-level), so do not sum them across the services that share it. Where a per-service buyer count is attributed, the assessment block and the ranking, it is divided pro-quota by the 62 services sharing the address and can be fractional: a declared convention, not an individually observed measure.
COMPLIANCE
11/11 checks pass · grade A- 402 payload captured
- accepts[] array present
- payTo address recoverable
- payTo at accepts[0].payTo (conformant shape)
- payTo is a valid on-chain address
- atomic price declared
- atomic price in a sane range
- asset (token) address declared
- network resolves to CAIP-2
- payment scheme declared
- served over HTTPS
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