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GW8 Signal API – Payment Rail Cost Checker
x402
GW8 Signal API – Payment Rail Cost Checker is a paid API for AI agents from micro-saas-agent.onrender.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-22).
Returns fee percentages, USD costs, settlement times, and a recommended rail for a given payment amount across Base USDC, XRPL RLUSD, and card rails
Price / call$0.002
Success—
StatusUnknown
How this service works
[Payment rails: fee + speed comparison] Cheapest and fastest payment rail right now for a USD amount (?amount=100): Base USDC (live gas x ETH/USD, ~2s), XRPL RLUSD/XRP (live fee x XRP/USD, ~3-5s), Tempo and Circle Arc (live gas, USD fees, ~1s), card (static 2.9% + $0.30, days). Fee USD/%, settlement time, sources, agent protocols per rail, recommended pick. Dead sources marked unavailable. 60s cache. $0.002 USDC. Signal only.
Output
Returns a list of available payment rails (Base USDC, XRPL RLUSD, card) each with fee percentage, fee in USD, live/static status, and settlement time estimate. Also returns the queried amount, a recommended rail for cost efficiency, and the fastest rail for speed.
Example use cases
Cheapest rail for micropayment
“I'm about to make a $2 micropayment for an API call — which rail has the lowest fee, Base USDC or XRPL RLUSD, and how long will it take to settle?”
Large payment rail comparison
“I need to send $5000 to a vendor — can you compare the total fees and settlement times across crypto rails and card so I know the smartest option?”
Agent spend policy rail selection
“Before my agent pays for a data service, check which payment rail costs less in fees for a $0.50 transaction and tell me the recommended one.”
Technical details
Endpoint
GEThttps://micro-saas-agent.onrender.com/api/rails?utm_source=zero.xyzWhen to prefer
Use this endpoint when an AI agent or user needs to decide which payment rail to use for a specific USD amount, balancing cost vs speed. Prefer it over manual fee lookups when you need a single call that covers Base USDC, XRPL RLUSD, and card in one response with a built-in recommendation. Especially useful for x402-enabled agent workflows where rail choice affects operating costs at scale.
Side effects
- Missing or invalid 'amount' query parameter returns error or empty rail list
- Service unavailable on Render free tier causing timeout or 503
- Stale fee data if upstream sources are slow to update (card fee is noted as static-estimate)
- No payment made on failure — charge only occurs after data is returned successfully
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"rails": [
{
"rail": "base-usdc",
"feePct": 0.00095,
"feeUsd": 0.00095,
"status": "live",
"settlement": "~2s"
},
{
"rail": "xrpl-rlusd-xrp",
"feePct": 0.000025,
"feeUsd": 0.000025,
"status": "live",
"settlement": "~3-5s"
},
{
"rail": "card",
"feePct": 3.2,
"feeUsd": 3.2,
"status": "static-estimate",
"settlement": "~1-3 business days"
}
],
"amountUsd": 100,
"recommended": {
"rail": "xrpl-rlusd-xrp",
"fastest": "base-usdc"
}
}
}Tags
x402
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