Live snapshot of the most liquid carbon credits retirable on Base
Live snapshot of the most liquid carbon credits retirable on Base: the top 3 Klima Protocol carbon classes and the top 3 Carbonmark marketplace listings, with USDC-per-tonne prices and tonnes available. Additionally, the additional endpoints to quote and retire carbon are included; query those endpoints for further discovery, quotes, and retirements. Query /.well-known, /openapi, and /discover to get started.
Answeringour last check, 2026-09-24
1 of 1checks answered this week
597 msmedian answer time
$0.001listed price per call
$0.001price 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
GET https://x402-retire-git-feat-paid-indexing-gate-and-openapi-carbonmark.vercel.app/api/catalog
| Category | Code and developer |
|---|---|
| Provider host | x402-retire-git-feat-paid-indexing-gate-and-openapi-carbonmark.vercel.app |
| 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 |
|---|---|---|---|---|
| 2026-09-24 | valid payment request | 402 | $0.001 | 597 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"additionalProperties": false,
"properties": {},
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"additionalProperties": false,
"properties": {
"asOf": {
"type": "string"
},
"classes": {
"items": {
"additionalProperties": false,
"properties": {
"carbonClassId": {
"type": "string"
},
"category": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"country": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"creditCount": {
"type": "number"
},
"liquidityTonnes": {
"type": "string"
},
"name": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"priceBasis": {
"const": "indicative",
"type": "string"
},
"priceUsdcPerTonne": {
"type": "string"
},
"priceUsdcPerTonneFormatted": {
"type": "string"
}
},
"required": [
"carbonClassId",
"name",
"category",
"country",
"priceUsdcPerTonne",
"priceUsdcPerTonneFormatted",
"priceBasis",
"liquidityTonnes",
"creditCount"
],
"type": "object"
},
"type": "array"
},
"endpoints": {
"additionalProperties": false,
"properties": {
"actionsRetire": {
"type": "string"
},
"certificate": {
"type": "string"
},
"discover": {
"type": "string"
},
"openapi": {
"type": "string"
},
"prepareAuth": {
"type": "string"
},
"prepareRetire": {
"type": "string"
},
"quote": {
"type": "string"
}
},
"required": [
"discover",
"quote",
"prepareRetire",
"prepareAuth",
"actionsRetire",
"certificate",
"openapi"
],
"type": "object"
},
"listings": {
"items": {
"additionalProperties": false,
"properties": {
"category": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"country": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"creditId": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"expiresAt": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"leftToSellTonnes": {
"type": "string"
},
"listingId": {
"type": "string"
},
"minFillTonnes": {
"type": "string"
},
"priceBasis": {
"const": "firm",
"type": "string"
},
"priceUsdcPerTonne": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
]
},
"priceUsdcPerTonneFormatted": {
"anyOf": [
{
"type": "string"
},