x402 listing doctor for sellers
x402 listing doctor for sellers: why a paid endpoint gets no buyers. Runs the x402 preflight, Coinbase's CDP validator, and presence checks in the CDP Bazaar and 402index, then returns concrete fixes: 402 before input validation, Bazaar metadata, description over 500 chars or instruction-like, slow or sleeping host, no settled sale yet. Input: endpoint URL, optionally 'POST <url>'. Deterministic, no LLM.
Answeringour last check, 2026-11-04
4 of 4checks answered this week
172 msmedian answer time
$0.005listed price per call
$0.005price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://minty-sprout.onrender.com/v1/x402-listing-doctor
| Category | Everything else |
|---|---|
| Provider host | minty-sprout.onrender.com |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-11-04 | valid payment request | 402 | $0.005 | 170 ms |
| 2026-11-03 | valid payment request | 402 | $0.005 | 174 ms |
| 2026-11-02 | valid payment request | 402 | $0.005 | 171 ms |
| 2026-11-01 | valid payment request | 402 | $0.005 | 174 ms |
Example input (from the provider)
{
"body": {
"input": "https://x402-preflight.nextill-pos.workers.dev/v1/preflight"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"properties": {
"input": {
"description": "URL of your paid x402 endpoint, optionally prefixed with GET or POST",
"maxLength": 8000,
"type": "string"
}
},
"required": [
"input"
],
"type": "object"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"cdp_validation": {
"type": "object"
},
"fixes": {
"items": {
"type": "string"
},
"type": "array"
},
"listed": {
"type": "object"
},
"verdict": {
"enum": [
"ok",
"warn",
"block"
]
}
},
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}