# Xynaptic Gas Fees

> Xynaptic Gas Fees is a paid API for AI agents from api.xynaptic.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-30).

Returns live gas prices for Ethereum and Base chains across slow, average, and fast tiers in Gwei plus estimated transfer cost

## Facts

- Endpoint: GET https://api.xynaptic.io/v1/crypto-gas-fees?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/xynaptic-gas-fees-29cff8e4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2kgFn8nkSuZioPOLpJouk

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 xynaptic-gas-fees-29cff8e4
```

Example prompt: What are the current gas fees on Ethereum and Base right now — show me slow, average, and fast Gwei prices so I can decide when to send my transaction?

## When to prefer this

Choose this endpoint when you need live, multi-chain gas fee data (Ethereum and Base) with tier breakdowns (slow/average/fast) in a single no-parameter GET call. Ideal for agents that need to automate transaction timing, display gas cost estimates, or trigger actions based on gas thresholds. Prefer it over on-chain RPC calls when you want a clean REST API without managing Web3 node connections.

## Known failure modes

- Upstream gas oracle unavailable — returns 5xx error if the data source is down
- Rate limiting — returns 429 if call quota exceeded
- Payment not fulfilled — returns 402 if x402 payment is not provided or fails
- Stale data — prices may lag by seconds during extreme network congestion

## How this service works

Xynaptic Gas Fees — live gas prices across chains (Ethereum, Base) with slow/average/fast tiers in Gwei + estimated transfer cost. GET no params. Plan your on-chain transaction timing.

## Output

A JSON response containing live gas price tiers (slow, average, fast) in Gwei for Ethereum and Base chains, along with an estimated transfer cost in USD or native token units, allowing agents to assess transaction cost and timing.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/xynaptic-gas-fees-29cff8e4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.xynaptic.io](https://www.zero.xyz/host/api.xynaptic.io/llms.txt)