# Oblique Markets Text Classifier

> Oblique Markets Text Classifier is a paid API for AI agents from api.oblique.markets, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Classifies a piece of text into one of 2–20 caller-supplied labels using an LLM, returning only a validated canonical label (never a hallucinated one) or a 502 error.

## Facts

- Endpoint: POST https://api.oblique.markets/api/v1/paid/classify
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/oblique-markets-text-classifier-139eba4e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tI3oSwIavDEnoTqnk2muF

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-text-classifier-139eba4e -d '<json body>'
```

Example prompt: Classify this support ticket — 'My order never arrived and I want a refund' — into one of these labels: billing, shipping, returns, technical, general. Make sure you only return one of those exact labels.

## When to prefer this

Choose this endpoint when you need guaranteed label fidelity — i.e., you cannot tolerate an LLM returning a label outside your predefined set. It is ideal for deterministic routing pipelines, compliance-sensitive categorization, or any workflow where a hallucinated label would cause a downstream error. Prefer it over a raw LLM call when you need a strict enum-like output with no free-text drift. It pays per call at $0.005 USDC, making it cost-effective for high-volume classification tasks that don't need a full generative response.

## Known failure modes

- 502 returned when the LLM cannot confidently map the text to any of the supplied labels — prevents hallucinated or out-of-set labels
- Input text is ambiguous or too short for any label to be meaningful — 502 or unexpected label
- Fewer than 2 or more than 20 labels supplied — likely a 4xx validation error
- Payment failure via x402 — endpoint refuses request before classification is attempted
- Latency spike if underlying LLM is under load — retries may be needed

## How this service works

Use when an agent needs classify. Returns Single-label text classification against 2-20 caller-supplied labels — reply validated against the label set, canonical label returned, 502 instead of hallucinated labels. $0.005.

## Output

A single canonical label drawn exactly from the caller-supplied label set. The response is validated against that set — if the LLM would otherwise produce something outside the list, the endpoint returns a 502 rather than a hallucinated label. Agents receive a clean, machine-readable string with no extra explanation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string",
   "description": "Text to classify; truncated to 8,000 characters"
  },
  "labels": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "description": "Candidate labels; exactly one is returned"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "label": "billing_issue",
  "model": "inclusionai/ling-3.0-flash"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/oblique-markets-text-classifier-139eba4e/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)