# Oblique Markets Chat Completion

> Oblique Markets Chat Completion is a paid API for AI agents from api.oblique.markets, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Provides a single OpenAI-compatible chat completion response per paid call, with no account or API key required, via x402 micropayment.

## Facts

- Endpoint: POST https://api.oblique.markets/api/v1/paid/chat-completion
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/oblique-markets-chat-completion-9e438dd3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_EOrh5cQk4hXlcEsI3UyrP

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 oblique-markets-chat-completion-9e438dd3 -d '<json body>'
```

Example prompt: Ask the AI: 'Summarize the following article in three bullet points: [article text]' — send it as a user message with a system prompt saying 'You are a concise summarizer' and limit the response to 300 tokens.

## When to prefer this

Choose this endpoint when an agent needs one-shot LLM inference without managing an OpenAI API key or opening a provider account. Ideal for autonomous agents operating on the x402 payment rail that need to pay per call in USDC rather than maintain subscription credentials. Best for bounded, single-turn or short multi-turn conversations within the 24,000 character and 600 token limits.

## Known failure modes

- Input exceeds 24,000 character limit — request rejected
- max_tokens exceeds 600 — response may be truncated or rejected
- Payment not processed or x402 header missing — 402 Payment Required error
- Malformed messages array (missing role or content fields) — 400 Bad Request
- Model unavailable or upstream provider error — 503 or 500 error

## How this service works

Use when an agent needs chat completion. Returns One bounded chat completion (standard messages request shape) per paid call, with no account to open and no provider key to hold; max 24,000 input characters and 600 output tokens. $0.01.

## Output

A single bounded chat completion response from an OpenAI-compatible model, containing the assistant's generated text reply. The response is capped at 600 output tokens and is returned synchronously after the x402 micropayment is processed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "enum": [
       "system",
       "user",
       "assistant"
      ],
      "type": "string"
     },
     "content": {
      "type": "string"
     }
    }
   }
  },
  "max_tokens": {
   "type": "integer"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": "chatcmpl_rep_example",
  "model": "inclusionai/ling-3.0-flash",
  "usage": {
   "total_tokens": 26,
   "prompt_tokens": 12,
   "completion_tokens": 14
  },
  "object": "chat.completion",
  "choices": [
   {
    "index": 0,
    "message": {
     "role": "assistant",
     "content": "x402 is a protocol for HTTP-native machine payments."
    },
    "finish_reason": "stop"
   }
  ],
  "upstream": "openrouter"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/oblique-markets-chat-completion-9e438dd3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.oblique.markets](https://www.zero.xyz/host/api.oblique.markets/llms.txt)