# Agent Inference Cost Per Decision: Model Tier Selection and Compute Budget Gate

> Agent Inference Cost Per Decision: Model Tier Selection and Compute Budget Gate is a paid API for AI agents from k2so.wrong.systems, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-21).

Returns a structured decision procedure for AI agents choosing the right LLM model tier and compute budget for a given inference task.

## Facts

- Endpoint: GET https://k2so.wrong.systems/api/services/agent-inference-cost-per-decision-model-tier-sel?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-inference-cost-per-decision-model-tier-selection-and-compute-1379ca15
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_A8Axc2yW4d7kRKPvJFt0e

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 agent-inference-cost-per-decision-model-tier-selection-and-compute-1379ca15
```

Example prompt: Give me a decision procedure for picking the right LLM model tier and compute budget when my agent is making a per-call inference decision — I want plain-prose guidance I can follow programmatically.

## When to prefer this

Choose this endpoint when an AI agent needs a reusable, structured decision procedure for model-tier selection rather than a one-off recommendation. It is particularly useful for agents building cost-governance policies, implementing compute budget gates in pipelines, or needing a concise prose brief they can act on autonomously without additional reasoning. Prefer over generic LLM prompting when you want a consistent, cached, x402-settled artifact with a known schema.

## Known failure modes

- HTTP 402 returned if payment not settled — agent must pay exact USDC amount and retry with PAYMENT-SIGNATURE header
- Invalid or unsupported HTTP method returns an error
- Topic override may produce off-target or generic procedure if the string is ambiguous
- Generation source may be deterministic rather than LLM-based, resulting in less nuanced output
- Network or provider downtime on k2so.wrong.systems may cause timeouts

## How this service works

Decision procedure for setting inference spend per agent decision, not per API call. Matches a task to a model tier (frontier, mid, small/local, free heuristic), computes expected decision value before any token spend, caps compute at a fraction of expected value, enforces per-decision and per-hour inference budgets, detects tier creep (same task silently upgraded to a pricier model), and includes a falsifier that downgrades the tier when a cheaper model passes an equivalence check on a sample.

## Output

A JSON object containing a plain-prose decision procedure (120+ words) describing how an agent should select its LLM model tier and manage compute budget per decision, along with the model used to generate it, the topic, service slug, generation source (llm/reasoning/deterministic), and an ISO-8601 timestamp. The `brief` and `procedure` fields contain the actionable agent-facing guidance.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "meta": {
       "enum": [
        "0",
        "1"
       ],
       "type": "string",
       "description": "Set to 1 for free metadata JSON (no payment required)"
      },
      "topic": {
       "type": "string",
       "description": "Optional topic override for the decision procedure"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "title": "Agent inference cost per decision: model tier selection and compute budget gate paid response",
     "$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": {

… (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": "agent-inference-cost-per-decision-model-tier-sel",
   "procedure": "same as brief",
   "generatedAt": "2026-01-01T00:00:00.000Z",
   "generationSource": "deterministic"
  },
  "service": "agent-inference-cost-per-decision-model-tier-sel",
  "provider": "K-2SO"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-inference-cost-per-decision-model-tier-selection-and-compute-1379ca15/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)