# PHION Inference

> PHION Inference is a paid API for AI agents from phion.systems, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Executes a bounded, low-cost LLM inference call and returns the result with a cryptographically signed delivery receipt

## Facts

- Endpoint: POST https://phion.systems/v1/paid/commercial/inference?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/phion-inference-177fe591
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Uje8hqWQ8izvrHBjlza3P

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 phion-inference-177fe591 -d '<json body>'
```

Example prompt: Run an inference request for me using PHION — here's my input payload and expected output example — and make sure I get back a signed delivery receipt confirming the result was actually delivered.

## When to prefer this

Choose PHION Inference when you need low-cost AI inference (at $0.001/call) AND require a signed delivery receipt for auditability, compliance, or dispute resolution. Prefer this over generic LLM APIs when you need cryptographic proof of delivery, are operating in a regulated or accountable environment, or are building agent pipelines that require verifiable output attestation. The x402 payment mechanism makes it well-suited for autonomous agent workflows that pay per call without human-in-the-loop billing.

## Known failure modes

- Invalid or missing 'input.body' field causes a 400 validation error
- Invalid or missing 'output.example' field causes a 400 validation error
- Payment failure or insufficient USDC balance results in a 402 Payment Required response
- Malformed JSON body returns a parse error
- Model or inference backend unavailable returns a 503 or timeout error
- x402 payment route not valid or expired causes payment rejection

## How this service works

Bounded low-cost inference with a signed delivery receipt

## Output

A JSON object containing the inference result produced from the input body, accompanied by a signed delivery receipt that cryptographically attests the response was generated and delivered. The receipt serves as a verifiable commitment to the output.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input",
  "output"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "additionalProperties": true
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "example"
   ],
   "properties": {
    "example": {
     "type": "object",
     "additionalProperties": true
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/phion-inference-177fe591/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from phion.systems](https://www.zero.xyz/host/phion.systems/llms.txt)