# Single-Edition Digital Delivery Control Procedure

> Single-Edition Digital Delivery Control Procedure is a paid API for AI agents from k2so.wrong.systems, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-19).

Returns a deterministic decision procedure for agents purchasing one-of-a-kind digital goods, covering uniqueness validation, single-redemption delivery verification, watermark binding checks, and duplicate-delivery refund/hold rules.

## Facts

- Endpoint: GET https://k2so.wrong.systems/api/services/single-edition-digital-delivery-control-procedur?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/single-edition-digital-delivery-control-procedure-db786ad6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_rGlyfaT-Cd7sSULsvv2g7

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 single-edition-digital-delivery-control-procedure-db786ad6
```

Example prompt: I'm about to buy a one-of-a-kind digital artwork through an x402 payment — can you run the single-edition delivery control procedure to verify the uniqueness claim, check that it hasn't already been redeemed, and tell me what to do if I get flagged as a duplicate delivery?

## When to prefer this

Choose this endpoint when an autonomous agent is about to purchase a one-of-a-kind digital good over x402 and needs a deterministic, step-by-step procedure to validate uniqueness claims, enforce single-redemption, check watermark binding, and resolve duplicate delivery disputes — particularly when the asset has no fungible equivalent and re-delivery would constitute fraud. Prefer over generic payment validation endpoints when the specific concerns are edition uniqueness and buyer-specific watermark enforcement.

## Known failure modes

- Handler error returns ok:false with no procedure prose — agent should retry or fall back to manual review
- Topic override not recognized — procedure may default to generic single-edition logic rather than asset-specific guidance
- Payment not confirmed (paid:false) — full procedure withheld; only metadata returned if meta=1 query param is set
- Stale or cached procedure — generatedAt timestamp should be checked to ensure procedure is current
- Network or upstream LLM failure — generationSource field absent or response malformed

## How this service works

Deterministic procedure for buyer agents purchasing one-of-a-kind digital goods over x402. Covers pre-payment uniqueness claim grading, controlled single-redemption delivery verification, watermark binding checks, and duplicate-delivery refund or hold rules.

## Output

A structured decision-procedure response including prose guidance for the agent, a uniqueness grade for the pre-payment claim, single-redemption delivery verification status, watermark binding check outcome, and applicable duplicate-delivery refund or hold rules. Also includes service slug, generation source (llm, reasoning, or deterministic), ISO-8601 timestamp, and payment confirmation fields.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "Single-edition digital delivery control procedure paid response",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "required": [
      "ok",
      "paid",
      "service",
      "provider",
      "result"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "paid": {
       "type": "boolean"
      },
      "result": {
       "type": "object",
       "required": [
        "ok",
        "service"
       ],
       "properties": {
        "ok": {
         "type": "boolean",
         "description": "Handler success"
        },
        "brief": {
         "type": "string",
         "description": "Decision procedure prose for agents"
        },
        "model": {
         "type": "string"
        },
        "topic": {
         "type": "string"
        },
        "service": {
         "type": "string",
         "description": "Service slug"
        },
        "procedure": {
         "type": "string"
        },
        "generatedAt": {
         "type": "string",
         "description": "ISO-8601 timestamp"
        },
        "generationSource": {
         "enum": [
          "llm",
          "reasoning",
          "deterministic"
         ],
         "type": "string"
        }
       }
      },
      "payment": {
       "type": "object",
       "properties": {
        "code": {
         "type": "string"
        },
        "payer": {
         "type": "string"
        },
        "detail": {
         "type": "string"
    
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "paid": true,
  "result": {
   "ok": true,
   "brief": "plain prose decision procedure (120+ words)",
   "model": "deepseek/deepseek-v4-flash-0731",
   "topic": "string topic",
   "service": "single-edition-digital-delivery-control-procedur",
   "procedure": "same as brief",
   "generatedAt": "2026-01-01T00:00:00.000Z",
   "generationSource": "deterministic"
  },
  "service": "single-edition-digital-delivery-control-procedur",
  "provider": "K-2SO"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/single-edition-digital-delivery-control-procedure-db786ad6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from k2so.wrong.systems](https://www.zero.xyz/host/k2so.wrong.systems/llms.txt)