← The evidence ledger
Evidence row 14859
Observed , by sync.x402_bazaar/1.
- Kind
- listing
- About
- source_record x402_bazaar:https://api.dripmetrics.ai/metrics/vpin
- Recorded
- Previous row
- None: the first of its kind about this subject
- Body SHA-256
- 0a17eca8a8e34a6f8b97a4641ca40e375477445f879c6cc77353c748f2e5d84d
- Leaf
- 0x5b264f9b2b9d13c9f53da18afa28a86099efd893bbe862b0dc0fad6ae99847bb
What was observed
{
"endpoints": [
[
"x402",
"https://api.dripmetrics.ai/metrics/vpin"
]
],
"name": "api.dripmetrics.ai/metrics/vpin",
"owner_address": "0xc9b70d8d342609437bc87ec3c877911a306d3e6a",
"raw": {
"accepts": [
{
"amount": "50000",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"maxTimeoutSeconds": 300,
"network": "eip155:8453",
"payTo": "0xc9b70D8d342609437bc87Ec3C877911a306d3e6A",
"scheme": "exact"
},
{
"amount": "50000",
"asset": "0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168",
"extra": {
"name": "Global Dollar",
"version": "1"
},
"maxTimeoutSeconds": 300,
"network": "eip155:4663",
"payTo": "0xc9b70D8d342609437bc87Ec3C877911a306d3e6A",
"scheme": "exact"
}
],
"description": "DripMetricsAI (api description at https://dripmetrics.ai/) provides on-demand market microstructure and risk metrics for agents and developers. Agents can pay per request via x402 and receive structured JSON metrics without subscriptions or API keys. VPIN measures volume-synchronized order-flow imbalance (an adverse-selection proxy, not a probability); see excessVpin. Discovery examples use the latest 30m window.",
"extensions": {
"bazaar": {
"info": {
"input": {
"method": "GET",
"queryParams": {
"exchange": "coinbase",
"pair": "BTC-USD",
"window": "30m"
},
"type": "http"
},
"output": {
"example": {
"components": {
"bucketSize": 5,
"buckets": 20,
"buyTrades": 50,
"buyVolume": 50,
"estimatedNullVpin": 0.35682482,
"excessVpin": -0.15682482,
"meanImbalance": 1,
"meanTradeContributionsPerBucket": 5,
"minimumTradeContributionsPerBucket": 5,
"minimumTradeCount": 100,
"oneSidedBuckets": 0,
"sellTrades": 50,
"sellVolume": 50,
"targetBuckets": 20,
"totalVolume": 100,
"tradeCount": 100
},
"computedAt": "2026-05-23T14:00:00.000Z",
"coverage": {
"completeFetch": true,
"coverageRatio": 1,
"effectiveWindowMinutes": 30,
"errorMessage": null,
"partialData": false,
"requestedWindowMinutes": 30
},
"exchange": "coinbase",
"firstTradeTime": "2026-05-23T13:00:02.000Z",
"lastTradeTime": "2026-05-23T13:59:58.000Z",
"metric": "vpin",
"pair": "BTC-USD",
"tradeCount": 100,
"value": 0.2,
"window": "30m"
},
"type": "json"
}
},
"schema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"additionalProperties": false,
"properties": {
"exchange": {
"description": "Exchange adapter to source recent trades from.",
"enum": [
"binance",
"coinbase",
"hyperliquid"
],
"type": "string"
},
"pair": {
"description": "Exchange-native trading pair symbol such as BTCUSDT, ETH-USD, BTC, or xyz:TSLA.",
"type": "string"
},
"window": {
"description": "Lookback window. Hyperliquid supports 30m and 1h; 2h and 3h are currently BTCUSDT/BTC-USD only.",
"enum": [
"30m",
"1h",
"2h",
"3h"
],
"type": "string"
}
},
"required": [
"pair",
"exchange",
"window"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"additionalProperties": false,
"properties": {
"benchmarkCoverage": {
"additionalProperties": false,
"properties": {
"completeFetch": {
"type": "boolean"
},
"coverageRatio": {
"maximum": 1,
"minimum": 0,
"type": "number"
},
"effectiveWindowMinutes": {
"minimum": 0,
"type": "number"
},
"errorMessage": {
"type": [
"string",
"null"
]
},
"partialData": {
"type": "boolean"
},
"requestedWindowMinutes": {
"minimum": 0,
"type": "number"
}
},
"required": [
"requestedWindowMinutes",
"effectiveWindowMinutes",
"coverageRatio",
"partialData",
"completeFetch",
"errorMessage"
],
"type": "object"
},
"components": {
"additionalProperties": false,
"properties": {
"bucketSize": {
"type": "number"
},
"buckets": {
"type": "integer"
},
"buyTrades": {
"type": "integer"
},
"buyVolume": {
"type": "number"
},
"estimatedNullVpin": {
"description": "Approximate finite-sample VPIN baseline under independent, equally likely buy/sell signs.",
"type": "number"
},
"excessVpin": {
"description": "Raw VPIN minus estimatedNullVpin; this signed value is not clamped at zero. Raw VPIN is sample-size dependent and comparable only within the same market and window, so use excessVpin and the bucket-density fields for broader comparisons.",
"type": "number"
},
"meanImbalance": {
"type": "number"
},
"meanTradeContributionsPerBucket": {
"type": "number"
},
"minimumTradeContributionsPerBucket": {
"type": "integer"
},
"minimumTradeCount": {
"type": "integer"
},
"oneSidedBuckets": {
"type": "integer"
},
"sellTrades": {
"type": "integer"
},
"sellVolume": {
"type": "number"
},
"targetBuckets": {
"type": "integer"
},
"totalVolume": {
"type": "number"
},
"tradeCount": {
"type": "integer"
}
},
"required": [
"buckets",
"bucketSize",
"meanImbalance",
"totalVolume",
"tradeCount",
"minimumTradeCount",
"targetBuckets",
"buyTrades",
"sellTrades",
"buyVolume",
"sellVolume",
"oneSidedBuckets",
"minimumTradeContributionsPerBucket",
"meanTradeContributionsPerBucket",
"estimatedNullVpin",
"excessVpin"
],
"type": "object"
},
"computedAt": {
"format": "date-time",
"type": "string"
},
"coverage": {
"additionalProperties": false,
"properties": {
"completeFetch": {
"type": "boolean"
},
"coverageRatio": {
"maximum": 1,
"minimum": 0,
"type": "number"
},
"effectiveWindowMinutes": {
"minimum": 0,
"type": "number"
},
"errorMessage": {
"type": [
"string",
"null"
]
},
"partialData": {
"type": "boolean"
},
"requestedWindowMinutes": {
"minimum": 0,
"type": "number"
}
},
"required": [
"requestedWindowMinutes",
"effectiveWindowMinutes",
"coverageRatio",
"partialData",
"completeFetch",
"errorMessage"
],
"type": "object"
},
"exchange": {
"enum": [
"binance",
"coinbase",
"hyperliquid"
],
"type": "string"
},
"firstTradeTime": {
"format": "date-time",
"type": "string"
},
"lastTradeTime": {
"format": "date-time",
"type": "string"
},
"metric": {
"type": "string"
},
"pair": {
"type": "string"
},
"tradeCount": {
"minimum": 1,
"type": "integer"
},
"value": {
"type": "number"
},
"window": {
"enum": [
"30m",
"1h",
"2h",
"3h"
],
"type": "string"
}
},
"required": [
"metric",
"pair",
"exchange",
"window",
"value",
"computedAt",
"tradeCount",
"firstTradeTime",
"lastTradeTime",
"coverage"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}
}
},
"lastUpdated": "2026-10-23T23:24:00.635Z",
"quality": {
"l30DaysTotalCalls": 10,
"l30DaysUniquePayers": 4,
"lastCalledAt": "2026-10-23T23:23:59.481Z"
},
"resource": "https://api.dripmetrics.ai/metrics/vpin",
"type": "http",
"x402Version": 2
},
"source": "x402_bazaar",
"summary": "DripMetricsAI (api description at https://dripmetrics.ai/) provides on-demand market microstructure and risk metrics for agents and developers. Agents can pay per request via x402 and receive structured JSON metrics without subscriptions or API keys. VPIN measures volume-synchronized order-flow imbalance (an adverse-selection proxy, not a probability); see excessVpin. Discovery examples use the latest 30m window."
}What the leaf hashes
{"body":"0a17eca8a8e34a6f8b97a4641ca40e375477445f879c6cc77353c748f2e5d84d","id":14859,"kind":"listing","method":"sync.x402_bazaar/1","observed_us":1793025318690089,"prev":null,"subject":"x402_bazaar:https://api.dripmetrics.ai/metrics/vpin","subject_kind":"source_record"}Proof
Its day has not closed yet. A day closes ten minutes after midnight UTC; the proof appears here then.