# Silverback Top Coins

> Silverback Top Coins is a paid API for AI agents from silverback-x402.onrender.com, paid per call via x402, $0.005/call, status down (last checked 2026-09-15).

Returns a ranked list of top cryptocurrency coins by market metrics on Base chain

## Facts

- Endpoint: POST https://silverback-x402.onrender.com/api/v1/top-coins
- Price: $0.005/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/silverback-x402-onrender-com-df935d9b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_x_fxMTg9tsaUbKN-x_A8s

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 silverback-x402-onrender-com-df935d9b -d '<json body>'
```

Example prompt: Can you pull up the top 10 coins on Base chain right now, sorted by market cap?

## When to prefer this

Use this endpoint when you need a quick ranked overview of top-performing coins on Base chain, especially for DeFi dashboards, trading research, or discovering trending tokens without needing deep security or liquidity analysis.

## Known failure modes

- Payment not received — 402 response requiring x402 USDC payment
- Invalid filter parameters — 400 bad request
- Service temporarily unavailable on Render — 503
- Empty result set if no coins match filter criteria
- Rate limit exceeded — 429 too many requests

## Output

A ranked list of top cryptocurrency coins with market data including price, market cap, volume, and token metadata for the leading assets on Base chain.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/silverback-x402-onrender-com-df935d9b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from silverback-x402.onrender.com](https://www.zero.xyz/host/silverback-x402.onrender.com/llms.txt)