# Perp Mark Index Premium Calculator

> Perp Mark Index Premium Calculator is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Computes the perpetual futures basis premium as (mark - index) / index in basis points from caller-supplied prices

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/perp-premium
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/perp-mark-index-premium-calculator-115bf5af
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_S527ocu_KP8gJ-AxynmdY

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 perp-mark-index-premium-calculator-115bf5af -d '<json body>'
```

Example prompt: What's the perp premium in basis points if the mark price is 68,450 and the index price is 68,200?

## When to prefer this

Choose this endpoint when you already have mark and index prices in hand and need a quick, deterministic basis-points computation without subscribing to live market feeds or managing API keys. It is ideal for advisory analytics, trade logging, or pre-trade basis checks inside automated agent workflows where capital decisions remain with the caller.

## Known failure modes

- Missing mark or index field returns a 4xx validation error
- index price of zero causes division-by-zero error
- Non-numeric values for mark or index result in schema validation failure
- Payment failure via x402 returns 402 Payment Required before computation occurs

## How this service works

Premium (mark-index)/index in bps. Call when monitoring perp basis without live feeds (caller prices). Returns premium_bps as deterministic JSON for $0.001 USDC via x402 on Base. First-party local math only—no RPC, live market feed, API keys, storage, or mediagen. Advisory only; the caller owns capital, risk, and production controls.

## Output

Returns a deterministic JSON object containing premium_bps, the calculated (mark - index) / index value expressed in basis points, with no external data dependencies

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "mark": {
   "type": "number",
   "description": "Perp mark price"
  },
  "index": {
   "type": "number",
   "description": "Index price"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "schema": "delx/util-perp-premium/v1",
  "premium_bps": 50
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/perp-mark-index-premium-calculator-115bf5af/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)