# x402 Agent Economy Lab Text Similarity API

> x402 Agent Economy Lab Text Similarity API is a paid API for AI agents from rqjzcd-ip-209-115-177-214.tunnelmole.net, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Computes semantic or lexical similarity between two text inputs, paid per call in real USDC on Base mainnet via x402.

## Facts

- Endpoint: POST https://rqjzcd-ip-209-115-177-214.tunnelmole.net/v1/similarity
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-agent-economy-lab-text-similarity-api-c2cf001d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pKwbL0TWy5etqgFCX_kmY

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 x402-agent-economy-lab-text-similarity-api-c2cf001d -d '<json body>'
```

Example prompt: Compare these two product descriptions for semantic similarity and give me a score: 'Wireless noise-cancelling headphones with 30-hour battery' and 'Bluetooth headphones that block ambient sound, up to 30 hours of playback'.

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call text similarity score without committing to a subscription-based NLP platform, especially in autonomous agent pipelines that can self-fund via USDC micropayments on Base mainnet. Useful when you want similarity as a standalone primitive rather than bundled into a larger embedding or search service.

## Known failure modes

- Missing or empty text field returns 400 Bad Request
- Payment not settled on Base mainnet causes 402 Payment Required
- Text inputs that are extremely long may be truncated or rejected
- Tunnelmole tunnel URL may be ephemeral and become unavailable
- Network timeout if tunnel relay is slow or overloaded

## How this service works

Machine-payable NLP micro-services: sentiment, entity extraction, summarization, report, batch. Paid per call in REAL USDC on Base mainnet.

## Output

Returns a numeric similarity score (typically 0–1) indicating how semantically or lexically close the two input texts are, allowing agents to rank, filter, or threshold based on relatedness.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-agent-economy-lab-text-similarity-api-c2cf001d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rqjzcd-ip-209-115-177-214.tunnelmole.net](https://www.zero.xyz/host/rqjzcd-ip-209-115-177-214.tunnelmole.net/llms.txt)