x-preflight

Live 402 challenge

Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.

{
  "call": "POST a draft post here with x402. The price is 10000 atomic units of USDC, which is $0.01, because USDC has 6 decimals. Returns a model read of the draft on top of the checks that are already free.",
  "never": "this never writes or rewrites your post, and nothing is stored.",
  "service": "x-preflight",
  "guarantee": "payment and a COMPLETE verdict, or no payment. This is a mechanism rather than a promise: settlement runs only after the handler returns, and only when it returns under 400. If the model read fails, the handler returns 503, which cancels the payment before it can settle.",
  "fast_option": "Send {\"brief\": true} to get the classification only: survival verdict, built_for, one_claim, anchored_in_public, negative_risk level, private_terms, and all eight gates. It drops the prose (why, anchor_note, changes, strongest_move) which is 78% of the generation, so it answers in SECONDS rather than tens of seconds. Same model, same reasoning, same price. If your client has a short timeout, use this.",
  "you_pay_for": "the model read only: visibility-filter risk, what the post is built for, and the strongest move. It is the one part that cannot be answered from published source.",
  "price_in_words": "10000 atomic = 0.01 USDC = one cent. NOT 10000 dollars. The accepts block carries atomic units because the x402 spec requires it, and it has no decimals field, so read this line.",
  "if_you_cannot_wait": "Either send {\"brief\": true} to this endpoint, which answers in seconds, or use the free endpoint: POST https://kevinhoff.com/api/grade with {\"dry\":true}. It answers in under a second, costs nothing, and returns every check read from the published ranking source. Only the model read is slow, and only the model read is paid.",
  "free_without_paying": "Every check read from X's open-sourced ranking code is free and unmetered at https://kevinhoff.com/api/grade with {\"dry\":true}: the eight gates, the structural consequences, the 29 action prices, the reply chain, the index windows. You do not need to pay for any of that, ever.",
  "how_long_this_takes": "TWENTY TO FORTY SECONDS, because the paid half is a model reading your draft. SET YOUR CLIENT HTTP TIMEOUT ABOVE 60 SECONDS. If your client gives up sooner you will be charged and will not see the verdict, because settlement happens on our side and does not depend on you still waiting. Coinbase awal defaults near 13 seconds and is too impatient for this door as shipped.",
  "how_to_check_the_guarantee": "Do not take the line above on trust. If you get a 503, look up the seller address on Base: there will be no transfer for it. If you get a 200, the body contains eight gates AND a model read with no error field, because anything less would have been a 503."
}

Accepts

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

[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2"
    },
    "payTo": "0x3A7292b88471691946D8D8856925e22246bed743",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 300
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "text": "the draft post you are about to publish on x.com"
        },
        "type": "http",
        "method": "POST",
        "bodyType": "json"
      },
      "output": {
        "type": "json",
        "example": {
          "gates": [
            {
              "n": 1,
              "src": "phoenixRankAllCandidateProcessor.strato:446-451",
              "head": "It can be found by strangers.",
              "name": "On the list",
              "state": "go"
            }
          ],
          "model": {
            "survival": {
              "verdict": "clear"
            },
            "built_for": "copy_link",
            "negative_risk": {
              "level": "low"
            }
          },
          "structural": [
            {
              "src": "phoenixRankAllCandidateProcessor.strato:446-451",
              "fact": "enters the pool",
              "detail": "An original or a quote is written to the index out-of-network readers are drawn from."
            }
          ]
        }
      }
    },
    "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": {
              "required": [
                "text"
              ],
              "properties": {
                "text": {
                  "type": "string",
                  "description": "The draft post. Never rewritten, never stored."
                },
                "brief": {
                  "type": "boolean",
                  "description": "OPTIONAL, defaults to false. True returns the classification only and drops the prose, which is 78% of the generation. Answers in seconds instead of tens of seconds, same model and same price. Use it if your client has a short timeout."
                },
                "post_kind": {
                  "enum": [
                    "original",
                    "reply",
                    "quote",
                    "repost"
                  ],
                  "type": "string",
                  "description": "OPTIONAL, defaults to original. A reply's parent is not in the text, so no tool can read this off the draft. Declare it only if it is not an original."
                },
                "all_video_over_10s": {
                  "type": "boolean",
                  "description": "OPTIONAL, defaults to false. Whether EVERY attachment is video running longer than ten seconds. One photo or one short clip makes this false."
                },
                "reader_follows_back": {
                  "type": "boolean",
                  "description": "OPTIONAL, defaults to false. Whether the reader follows the author back. Decides in-network versus out-of-network, which changes the reply chain."
                },
                "followers_under_1000": {
                  "type": "boolean",
                  "description": "OPTIONAL, defaults to false. Whether the author is under the small-account cap that the one per-batch lift applies to."
                }
              }
            },
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "POST"
              ],
              "type": "string"
            },
            "bodyType": {
              "enum": [
                "json",
                "form-data",
                "text"
              ],
              "type": "string"
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object",
              "required": [
                "gates",
                "structural",
                "model"
              ],
              "properties": {
                "gates": {
                  "type": "array",
                  "items": {
                    "type": "object",
                    "required": [
                      "n",
                      "state",
                      "src"
                    ],
                    "properties": {
                      "n": {
                        "type": "number"
                      },
                      "src": {
                        "type": "string"
                      },
                      "head": {
                        "type": "string"
                      },
                      "name": {
                        "type": "string"
                      },
                      "state": {
                        "enum": [
                          "go",
                          "stop",
                          "open",
                          "call"
                        ],
                        "type": "string"
                      }
                    }
                  },
                  "description": "The eight gates in the order X runs them, each with a state and the source line it is read from."
                },
                "model": {
                  "type": "object",
                  "description": "The paid half: the read of the draft itself."
                },
                "structural": {
                  "type": "array",
                  "items": {
                    "type": "object",
                    "required": [
                      "fact",
                      "src"
                    ],
                    "properties": {
                      "src": {
                        "type": "string"
                      },
                      "fact": {
                        "type": "string"
                      },
                      "detail": {
                        "type": "string"
                      }
                    }
                  },
                  "description": "Consequences that need no model: branches in X's published source."
                }
              }
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog

2026-09-14 19:52Z

Last indexed by Roundhouse

2026-09-24 10:00Z

Last enriched (probe, favicon, geo)

2026-09-21 19:15Z

x402 version

2

Max timeout

300s

Liveness probe

HTTP 402