# Per-Rail Agent Payment Fee Comparison Procedure

> Per-Rail Agent Payment Fee Comparison Procedure is a paid API for AI agents from k2so.wrong.systems, paid per call via x402, $0.002/call, status down (last checked 2026-10-31).

Returns a blunt, LLM-generated decision procedure comparing live fee structures (priority fee, network fee, facilitator fee, settlement time) across Base, Solana, XRPL, TRON, Casper, and CSPR payment rails for AI agents.

## Facts

- Endpoint: GET https://k2so.wrong.systems/api/services/live-per-rail-agent-payment-fee-data-comparable?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: down
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/per-rail-agent-payment-fee-comparison-procedure-4c6a0119
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qddh-QMwW8jYDndIYEb6F

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 per-rail-agent-payment-fee-comparison-procedure-4c6a0119
```

Example prompt: Pull me a live fee comparison across Base, Solana, XRPL, TRON, Casper, and CSPR — I need a blunt decision procedure showing priority fees, network fees, facilitator fees, and settlement time tiers so I know which rail is cheapest for my agent's next payment.

## When to prefer this

Choose this endpoint when an AI agent needs a structured, blunt decision procedure (not marketing) comparing fee costs and settlement times across multiple blockchain payment rails simultaneously — especially Base, Solana, XRPL, TRON, Casper, and CSPR. It is well-suited for agents that need to autonomously select the cheapest or fastest rail at payment time. Prefer this over manual fee lookups when you need all rails in one call with facilitator fee context included. Avoid if you need deterministic real-time on-chain fee data guaranteed to the second, as generation may use reasoning rather than live RPC queries.

## Known failure modes

- Payment not submitted or rejected — endpoint returns 402 requiring USDC payment before content is delivered
- LLM generation failure — result.ok is false, brief may be empty or partial
- Stale data — fee data may not reflect real-time on-chain conditions if generation source is cached
- Invalid query parameter — unsupported meta or topic values may be ignored silently
- Network timeout — fast latency profile but upstream LLM calls may occasionally exceed response budget

## How this service works

Paid agent-facing brief on live per-rail agent payment fee data: comparable fee structure for a payment across Base, Solana, XRPL, TRON, Casper, CSPR, with priority fee / network fee / facilitator fee / settlement time tiers · Build a decision procedure or schema for: live per-rail agent payment fee data: comparable fee structure for a payment across Base, Solana, XRPL, TRON, Casper, CSPR, with priority fee / network fee / -0. Blunt decision procedure, not marketing.

## Output

A structured JSON response containing a prose decision procedure ('brief') written by an LLM or reasoning system, comparing fee structures (priority fee, network fee, facilitator fee, settlement time tiers) across Base, Solana, XRPL, TRON, Casper, and CSPR. Also includes service slug, model used, generation source (llm/reasoning/deterministic), ISO-8601 generation timestamp, and payment confirmation metadata.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "Per-rail agent payment fee comparison procedure paid response",
     "$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)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/per-rail-agent-payment-fee-comparison-procedure-4c6a0119/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)