# Oblique Markets ZenMux Chat Completion

> Oblique Markets ZenMux 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 2026-09-15).

Executes a single OpenAI-compatible chat completion via ZenMux (Oblique's inference router), capped at 24,000 input characters and 600 output tokens

## Facts

- Endpoint: POST https://api.oblique.markets/api/v1/paid/rep-cheaptokens-buy
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/oblique-markets-zenmux-chat-completion-ce5644d5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fuJs2yv6jxlEAZuvMYgOC

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-zenmux-chat-completion-ce5644d5 -d '<json body>'
```

Example prompt: Send this conversation to the ZenMux chat endpoint — system prompt: 'You are a concise assistant', user message: 'Summarize the key risks of stablecoin depegging in under 300 words' — and give me the response, keeping output under 300 tokens.

## When to prefer this

Choose this endpoint when you need a single, bounded, pay-per-call LLM inference without managing API keys or subscriptions — ideal for agent workflows that need occasional LLM calls billed at $0.01 USDC per call via x402 micropayment. Best for short prompts and brief responses (under 600 tokens). Prefer over OpenAI directly when you want pay-as-you-go crypto micropayment billing with no account setup, or when building autonomous agents on Base that already handle x402 payments.

## Known failure modes

- Input exceeds 24,000 character limit — request rejected with error
- max_tokens exceeds 600 — clamped or rejected
- Malformed messages array (missing role or content fields) — validation error
- Payment not processed or x402 payment header missing — 402 Payment Required
- ZenMux backend unavailable — 503 or timeout
- Empty messages array — error response

## How this service works

Use when an agent needs rep cheaptokens buy. Returns One bounded OpenAI-compatible chat completion via ZenMux, the honest Oblique equivalent of CheapTokens AI inference access; max 24,000 input characters and 600 output tokens. $0.01.

## Output

Returns an OpenAI-compatible chat completion response object containing the assistant's generated text message, limited to 600 output tokens. The response includes the message content and standard completion metadata such as token usage counts.

## 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"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/oblique-markets-zenmux-chat-completion-ce5644d5/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)