Roundhouse

API Direct

Search Substack publications by name or keyword.

SearchUnknowneip155:8453Exactvia cdp
https://x402.apidirect.io/v1/substack/publications
Substack
Settlements · 30d
169
No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days.
$1.00
Verified settled volume
169 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0040
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-10-25 12:23Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x5d07Cc2a0FB4Eb123A525CA0b51cf6fB485014fc

The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider

The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.

Accepts

The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.

0.004USDC≈ $0.004 USD
on Base · exact scheme

Pay 0.004 USDC on Base to 0x5d07…014fc. The signed payment is good for 15 minutes.

Paid to
0x5d07…014fc
USD Coin contract
0x8335…02913
Payment window
15 minutes
As published
4000 smallest units
0.004USDC≈ $0.004 USD
on Base · upto scheme

Pay 0.004 USDC on Base to 0x5d07…014fc. The signed payment is good for 15 minutes.

Paid to
0x5d07…014fc
USD Coin contract
0x8335…02913
Payment window
15 minutes
As published
4000 smallest units
The catalog’s raw entry
[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0x5d07Cc2a0FB4Eb123A525CA0b51cf6fB485014fc",
    "amount": "4000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 900
  },
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2",
      "facilitatorAddress": "0x8CDA367232d78c067116e3260da881d2da8ffa39",
      "assetTransferMethod": "permit2"
    },
    "payTo": "0x5d07Cc2a0FB4Eb123A525CA0b51cf6fB485014fc",
    "amount": "4000",
    "scheme": "upto",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 900
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "type": "http",
        "method": "GET",
        "queryParams": {
          "query": "crypto"
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "GET",
                "HEAD",
                "DELETE"
              ],
              "type": "string"
            },
            "queryParams": {
              "type": "object",
              "required": [
                "query"
              ],
              "properties": {
                "page": {
                  "type": "integer",
                  "default": 1,
                  "maximum": 4,
                  "minimum": 1,
                  "description": "Page number for pagination (1-4). Each page returns up to 20 publications."
                },
                "query": {
                  "type": "string",
                  "maxLength": 500,
                  "description": "Search keyword (max 500 characters)."
                },
                "language": {
                  "type": "string",
                  "maxLength": 2,
                  "minLength": 2,
                  "description": "Two-letter language code, e.g. es, to rank publications in that language first"
                }
              }
            }
          },
          "additionalProperties": false
        }
      }
    }
  },
  "eip2612GasSponsoring": {
    "info": {
      "version": "1",
      "description": "The facilitator accepts EIP-2612 gasless Permit to Permit2 canonical contract."
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "from",
        "asset",
        "spender",
        "amount",
        "nonce",
        "deadline",
        "signature",
        "version"
      ],
      "properties": {
        "from": {
          "type": "string",
          "pattern": "^0x[a-fA-F0-9]{40}$",
          "description": "The address of the sender."
        },
        "asset": {
          "type": "string",
          "pattern": "^0x[a-fA-F0-9]{40}$",
          "description": "The address of the ERC-20 token contract."
        },
        "nonce": {
          "type": "string",
          "pattern": "^[0-9]+$",
          "description": "The current EIP-2612 nonce of the sender."
        },
        "amount": {
          "type": "string",
          "pattern": "^[0-9]+$",
          "description": "The amount to approve (uint256)."
        },
        "spender": {
          "type": "string",
          "pattern": "^0x[a-fA-F0-9]{40}$",
          "description": "The address of the spender (Canonical Permit2)."
        },
        "version": {
          "type": "string",
          "pattern": "^[0-9]+(\\.[0-9]+)*$",
          "description": "Schema version identifier."
        },
        "deadline": {
          "type": "string",
          "pattern": "^[0-9]+$",
          "description": "The timestamp at which the signature expires."
        },
        "signature": {
          "type": "string",
          "pattern": "^0x[a-fA-F0-9]+$",
          "description": "The 65-byte concatenated signature (r, s, v) as a hex string."
        }
      }
    }
  }
}

Provenance

Seen in the source catalog
2026-10-25 12:23Z
Last indexed by Roundhouse
2026-10-26 19:30Z
Last enriched (probe, favicon, geo)
—
x402 version
2
Max timeout
900s
Liveness probe
Not probed
Report

Hand this page to an agent

Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.

GET api.roundhouseai.io/v0/endpoints

No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days. Verified volume counts only settlements with an on-chain EIP-3009 marker.

Open skill.md
Show the prompt
Using Roundhouse, look up the x402 service API Direct and tell me whether it is
worth paying: what a call costs, whether the endpoint answered when last probed, and what
its payment record actually shows.

curl -s 'https://api.roundhouseai.io/v0/endpoints?q=API%20Direct'
curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>'

Then call it: read the price from the live 402 at https://x402.apidirect.io/v1/substack/publications, never from
a cached figure, and pay with an x402 client.

The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except
/v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at
GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at
https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further.

If you do not have Roundhouse tools or skills installed, read
https://roundhouseai.io/skill.md first — it is the whole procedure.