# SigmaGrid Registry – Spread Signal

> SigmaGrid Registry – Spread Signal is a paid API for AI agents from api.sigmagrid.app, paid per call via x402, $0.02/call, status down (last checked 2026-10-12).

Returns a real-time quantitative spread signal for a given ticker, gated via the x402 micropayment protocol for algorithmic trading use.

## Facts

- Endpoint: POST https://api.sigmagrid.app/v1/spread/%7Bticker%7D?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: down
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sigmagrid-registry-spread-signal-30f30628
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_O8k74ZJefxvf3Mt6HvtS8

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 sigmagrid-registry-spread-signal-30f30628 -d '<json body>'
```

Example prompt: Pull the current spread signal for TSLA from SigmaGrid so I can feed it into my algo trading strategy.

## When to prefer this

Choose this endpoint when you need real-time spread or microstructure signals for a specific ticker to feed into an algorithmic or quantitative trading system. Best suited for agents executing per-call micropayment workflows via x402 where low per-query cost ($0.02 USDC) matters. Prefer over REST market data aggregators when the x402 pay-per-call model fits your agent's architecture.

## Known failure modes

- Invalid or unrecognized ticker symbol — 404 or validation error
- Payment not authorized or insufficient USDC balance — 402 Payment Required
- Ticker market is closed or no real-time data available — possible 503 or empty response
- Rate limit exceeded — 429 Too Many Requests
- Malformed request body — 400 Bad Request

## How this service works

Real-time quantitative signals for algorithmic trading, gated via the x402 payment protocol.

## Output

Returns a real-time quantitative spread signal for the requested ticker, likely including spread value, timestamp, and related microstructure metrics useful for algorithmic trading decisions. Each call costs $0.02 USDC via x402 payment.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sigmagrid-registry-spread-signal-30f30628/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.sigmagrid.app](https://www.zero.xyz/host/api.sigmagrid.app/llms.txt)