# SYNTHORA Macro Surprise Index

> SYNTHORA Macro Surprise Index is a paid API for AI agents from api.hergertsynthora.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-14).

Computes a z-score surprise index for the latest ECB macro data prints (HICP inflation, MRR policy rate, 10Y yield) relative to the trailing 12-change distribution, flagging strong or moderate surprises in real time.

## Facts

- Endpoint: POST https://api.hergertsynthora.com/v1/macro-surprise
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synthora-macro-surprise-index-8b85bfa1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dmcTLUcRAroyBtD3PyrwC

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 synthora-macro-surprise-index-8b85bfa1 -d '<json body>'
```

Example prompt: Can you check the SYNTHORA macro surprise index for ETH right now and tell me if the latest ECB data print — inflation, policy rate, or 10Y yield — triggered a strong or moderate surprise signal?

## When to prefer this

Choose this endpoint when you need a real-time, statistically grounded signal for whether the latest ECB macro data release (inflation, policy rate, or 10Y yield) is surprising relative to recent history. It is purpose-built for eurozone macro surprise detection with Ed25519-signed responses for auditability. Prefer it over generic news or sentiment endpoints when you need a quantitative z-score rather than a qualitative assessment, and over Fed-focused tools (like SOFR/EFFR endpoints) when your focus is ECB/eurozone data.

## Known failure modes

- Missing or invalid asset symbol returns an error or empty result
- Partial degradation: one or more ECB series may be unavailable, returning partial data
- Insufficient trailing data (fewer than 12 prior changes) may reduce z-score reliability
- Payment failure via x402 if wallet balance is insufficient after 3 free calls
- Invalid X-WALLET header may cause free-tier authentication failure
- ECB data feed delay may cause stale z-scores during publication lag windows

## How this service works

SYNTHORA macro surprise index: z-score of the latest change vs the trailing 12-change distribution for official ECB series (HICP inflation, MRR policy rate, 10Y yield). Flags strong/moderate surprises the moment official data prints. Partial degradation, Ed25519-signed. First 3 calls FREE per wallet via X-WALLET header. 0.05 USDC via x402 on Base.

## Output

Returns a z-score quantifying how surprising the latest ECB data change is relative to the trailing 12-change distribution, along with a categorical flag (strong or moderate surprise) for each of the three official ECB series: HICP inflation, MRR policy rate, and 10Y yield. Response is Ed25519-signed and supports partial degradation if some series are unavailable.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "asset": {
   "type": "string",
   "description": "asset symbol e.g. BTC/ETH"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synthora-macro-surprise-index-8b85bfa1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.hergertsynthora.com](https://www.zero.xyz/host/api.hergertsynthora.com/llms.txt)