{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://smklog.com/developers/schemas/checkout-session.schema.json",
  "title": "CheckoutSession",
  "type": "object",
  "description": "A payment session, not a charge: the amount and the handoff URL where the human pays. The amount is a live quote at this moment, not a hold or a reservation, and no money moves until the human completes the page.",
  "required": [
    "intent",
    "amount",
    "currency",
    "handoff_url"
  ],
  "properties": {
    "intent": {
      "type": "string",
      "enum": [
        "session"
      ],
      "description": "Always \"session\" — this operation never charges"
    },
    "session_id": {
      "type": [
        "string",
        "null"
      ],
      "pattern": "^as_[A-Za-z0-9-]{8,80}$",
      "description": "Handle for getCheckoutStatus, shaped as_ plus a UUID, good for 30 days. Null only when the session record could not be stored."
    },
    "created": {
      "type": "boolean",
      "description": "Which branch ran: true when this call created the session, false when it updated the session already stored under your external_id. Always true without external_id. Absent only when session_id is null, because then nothing was stored."
    },
    "external_id": {
      "type": "string",
      "description": "The external_id you sent, echoed back; absent when you sent none."
    },
    "method": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Payment rails behind the checkout, e.g. stripe, card"
    },
    "amount": {
      "type": "number",
      "description": "Live-quoted checkout total for the anchored service, USD"
    },
    "currency": {
      "type": "string",
      "enum": [
        "USD"
      ],
      "description": "ISO currency, USD"
    },
    "service": {
      "type": "string",
      "description": "The service the amount is anchored to"
    },
    "handoff_url": {
      "type": [
        "string",
        "null"
      ],
      "format": "uri",
      "description": "Opens the SMKlog checkout prefilled with this shipment; null on a dry run"
    },
    "dry_run": {
      "type": "boolean",
      "description": "True when the call was a dry run: priced and validated, nothing stored, session_id and handoff_url null."
    },
    "callback_url": {
      "type": "string",
      "format": "uri",
      "description": "The webhook URL stored on the session; absent when none is stored."
    },
    "callback_secret": {
      "type": "string",
      "description": "Present only in the answer that generated it (callback_url sent without callback_secret): the HMAC key the X-Smklog-Signature header is computed with. Shown once."
    },
    "identified_product_title": {
      "type": "string",
      "description": "What the estimator understood the item to be"
    },
    "quote_reused": {
      "type": "boolean",
      "description": "True when the amount came from a quote_id you supplied, so no carrier call was spent"
    },
    "note": {
      "type": "string",
      "description": "Standing caveats: live quote, human confirms consents and pays"
    }
  },
  "x-provenance": {
    "method": "published",
    "publisher": "SMKlog (SMKLOG-2022 LLC)",
    "source": "https://quote-api.smklog.com/openapi.json",
    "published": "2026-10-19"
  }
}