# SameDayDesk Payment Offer Preflight

> SameDayDesk Payment Offer Preflight is a paid API for AI agents from agents.samedaydesk.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Inspects a public HTTPS endpoint to detect, parse, and evaluate x402 and MPP payment offers before an agent commits to payment.

## Facts

- Endpoint: GET https://agents.samedaydesk.com/gateway/commerce/payment-offer-preflight
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/samedaydesk-payment-offer-preflight-1921e137
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Wy3mHZfHkMxbr778GoO1G

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability samedaydesk-payment-offer-preflight-1921e137
```

Example prompt: Before my agent pays anything, check what payment offers are on https://api.example.com/some-paid-endpoint — tell me whether the offer is parseable, which protocols it supports like x402 or MPP, how many offers there are, and whether anything looks off.

## When to prefer this

Use this endpoint when an AI agent needs to inspect and validate payment terms on any public HTTPS route before committing funds, especially for x402 or MPP machine-payable APIs. It is the right choice when you need a deterministic, no-side-effect preflight that parses offer structure, checks parity between protocols, and validates the response contract — as opposed to actually executing a payment or just detecting whether a 402 header is present.

## Known failure modes

- URL is not publicly accessible or requires credentials — endpoint cannot inspect it
- URL does not serve HTTP payment challenges — decision returns no_parseable_offer
- Malformed or non-HTTPS URL provided — validation error on input
- Endpoint returns ambiguous or conflicting payment headers — decision returns review_required
- Target URL is unreachable or times out — error response with no decision
- Payment offer schema version mismatch — findings array contains warnings

## How this service works

Deterministic agent APIs for web and company intelligence, repository security, agent-work economics, machine-service discoverability, payment preflight and settlement proof, wallet context, and Morpho decision evidence. Pay per call through Base x402 or native MPP, with a Circle Gateway Nanopayments path for gasless batched USDC.

## Output

Returns a structured object with a boolean ok, a decision enum (parseable_offer, review_required, or no_parseable_offer), an array of normalized payment offers, the count of offers, the protocols detected (x402, MPP), a parity comparison object, catalog coherence details, the response contract the endpoint claims to return, how to acquire that contract, an array of findings/warnings, boundary conditions, and a checkedAt timestamp.

## Request schema (JSON Schema)

```json
{
 "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": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri",
       "maxLength": 2048,
       "description": "Exact public HTTPS GET URL to inspect. Credential-like query keys, fragments, unresolved parameters, local hosts, redirects, and non-public IPs are rejected."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "ok",
      "product",
      "version",
      "checkedAt",
      "target",
      "decision",
      "protocols",
      "offerCount",
      "offers",
      "parity",
      "catalogCoherence",
      "responseContract",
      "responseContractAcquisition",
      "findings",
      "boundary"
     ],
     "properties": {
      "ok": {
       "type": "boolean",
       "const": true
      },
      "offers": {
       "type": "array"
      },
      "parity": {
       "type": "object"
      },
      "target": {
       "type": "object"
      },
      "product": {
       "type": "string",
       "const": "samedaydesk-payment-offer-preflight"
      },
      "version": {
       "type": "string",
       "const": "1.2.0"
      },
      "boundary": {
       "type": "object"
      },
      "decision": {
       "enum": [
        "parseable_offer",
        "review_required",
        "no_parseable_offer"
       ],
       "type": "string"
      },
      "findings": {
       "type": "array"
      },
      "checkedAt": {
       "type": "string",
       "format": "date-time"
      },
      "protocols": {
       "type": "array",
       "items": {
        "enum": [
         "mpp",
         "x402"
        ],
        "type": "string"
       }
      },
      "offerCount": {
       "type": "integer",
       "minimum": 0
      },
      "catalogCoherence": {
       "type": "array"
      },
      "responseContract": {
       "type": "o
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "offers": [
   {
    "valid": true,
    "intent": "exact",
    "scheme": "exact",
    "network": "eip155:8453",
    "protocol": "x402",
    "amountAtomic": "20000"
   }
  ],
  "parity": {
   "compared": true,
   "consistent": true,
   "driftFields": []
  },
  "target": {
   "url": "https://agents.samedaydesk.com/defi/morpho-position?address=0x8ee9c15c3e5332cbc6ef39a2bb036c63c6549b6e",
   "method": "GET",
   "httpStatus": 402
  },
  "product": "samedaydesk-payment-offer-preflight",
  "version": "1.2.0",
  "boundary": {
   "paymentSent": false,
   "paymentSigned": false,
   "credentialsUsed": false,
   "redirectsFollowed": false,
   "openApiDocumentRead": true,
   "targetResponseBodyRead": false
  },
  "decision": "parseable_offer",
  "findings": [],
  "checkedAt": "2026-08-10T20:00:00.000Z",
  "protocols": [
   "mpp",
   "x402"
  ],
  "offerCount": 2,
  "catalogCoherence": [],
  "responseContract": {
   "decision": "admissible",
   "exampleStatus": "structurally_consistent",
   "requiredPaths": [
    "ok",
    "title",
    "url"
   ],
   "requiredFields": [
    "ok",
    "title",
    "url"
   ],
   "runtimeResponseVerified": false
  },
  "responseContractAcquisition": {
   "path": "/openapi.json",
   "maxBytes": 1000000,
   "attempted": true,
   "sameOrigin": true,
   "documentRead": true,
   "credentialsUsed": false,
   "redirectsFollowed": false,
   "targetResponseBodyRead": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/samedaydesk-payment-offer-preflight-1921e137/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agents.samedaydesk.com](https://www.zero.xyz/host/agents.samedaydesk.com/llms.txt)