# auto-fiat Model Selector

> auto-fiat Model Selector is a paid API for AI agents from af-x402.auto-fiat.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-28).

Returns the cheapest AI model meeting a specified quality threshold, plus the top 10 models ranked by value

## Facts

- Endpoint: GET https://af-x402.auto-fiat.workers.dev/v1/models/best?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/auto-fiat-model-selector-179c86bb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_V6dvtxYOrv1UytokGz-Ox

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 auto-fiat-model-selector-179c86bb
```

Example prompt: What's the cheapest AI model that scores at least 80 on quality for a general task, with a max price of 5000? Give me the best pick and the top 10 by value.

## When to prefer this

Use this endpoint when you need to programmatically select the most cost-effective AI model for a task without manually comparing provider pricing pages. It is especially valuable in automated pipelines that need to dynamically pick a model based on quality requirements and budget constraints, or when building cost-aware AI orchestration systems.

## Known failure modes

- No model meets the specified min_score threshold — 'best' returns null
- max_price set too low — no qualifying models found, best is null and top10 may be empty
- Invalid query parameter values (e.g. min_score > 100) — validation error
- Payment failure or missing x402 payment header — 402 Payment Required
- Service unavailable or worker timeout — 5xx error

## How this service works

Cheapest model meeting a quality bar and top 10 by value

## Output

Returns a JSON object with two fields: 'best', which is the single cheapest model meeting the requested quality bar (or null if none qualify), and 'top10', an array of up to 10 model objects ranked by value. Each model object contains pricing and quality 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "task": {
       "enum": [
        "general",
        "json"
       ],
       "type": "string"
      },
      "max_price": {
       "type": "number",
       "maximum": 100000,
       "minimum": 0
      },
      "min_score": {
       "type": "number",
       "maximum": 100,
       "minimum": 0
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "best",
      "top10"
     ],
     "properties": {
      "best": {
       "type": [
        "object",
        "null"
       ]
      },
      "top10": {
       "type": "array",
       "items": {
        "type": "object"
       }
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/auto-fiat-model-selector-179c86bb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from af-x402.auto-fiat.workers.dev](https://www.zero.xyz/host/af-x402.auto-fiat.workers.dev/llms.txt)