# DEX Spread Anomaly Feed

> DEX Spread Anomaly Feed is a paid API for AI agents from api.agentfeeds.jp, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns DEX trading pair spread anomaly events where the 1-minute absolute spread exceeded the trailing 30-day 99th-percentile baseline, with descriptive statistics.

## Facts

- Endpoint: GET https://api.agentfeeds.jp/v1/dex/spreads/anomalies
- 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/dex-spread-anomaly-feed-6d17d44a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NoVZ-I8LxX-bnN-AbND_k

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 dex-spread-anomaly-feed-6d17d44a
```

Example prompt: Show me the latest 50 DEX spread anomaly events for the ETH/USDC pair since 2025-01-01 — I want to see cases where the 1-minute spread blew past the 30-day p99 baseline.

## When to prefer this

Use this endpoint when you need to identify specific historical moments of abnormal DEX spread activity relative to a statistical baseline, particularly for market surveillance, anomaly detection pipelines, or post-hoc analysis of liquidity stress events on decentralized exchanges. Prefer over the bulk historical window endpoint when you want pre-filtered anomaly events rather than raw 1-minute statistics.

## Known failure modes

- Invalid or unsupported pair symbol returns empty results or 400 error
- since timestamp in wrong format returns 400 validation error
- limit value outside 1-500 range returns 400 error
- Payment not provided or invalid returns 402 Payment Required
- Upstream data unavailability may return 503 or stale data

## How this service works

Spread anomaly events where 1-minute |spread| exceeded the trailing 30-day p99 baseline. Descriptive statistics only; not investment advice. Free 15-min-delayed sample: /v1/sample/dex.spread_anomalies

## Output

A list of spread anomaly events for the requested trading pair, each representing a 1-minute interval where the absolute spread exceeded the trailing 30-day 99th-percentile threshold, with descriptive statistics per event. Up to 500 events can be returned per call, optionally filtered by pair and start timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "pair": {
       "type": "string"
      },
      "limit": {
       "type": "integer",
       "description": "1-500, default 100"
      },
      "since": {
       "type": "string",
       "description": "ISO timestamp filter"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": [
   {
    "id": 1,
    "ts": "2026-07-19T03:09:00Z",
    "note": "12 samples in minute",
    "pair": "WETH/USDC",
    "venue_a": "uniswap_v3_base_005",
    "venue_b": "aerodrome_base",
    "spread_bps": 14.2,
    "p99_baseline": 9.8
   }
  ],
  "kind": "factual_data",
  "product": "dex.spread_anomalies"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/dex-spread-anomaly-feed-6d17d44a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.agentfeeds.jp](https://www.zero.xyz/host/api.agentfeeds.jp/llms.txt)