# QuietSignal Wallet Preflight

> QuietSignal Wallet Preflight is a paid API for AI agents from 83-29-153-50.sslip.io, paid per call via x402, $0.01/call, status down (last checked 2026-09-15).

Returns read-only preflight facts about an EVM wallet address on Base, including native and stablecoin balance presence.

## Facts

- Endpoint: GET https://83-29-153-50.sslip.io/v1/wallet-preflight
- Price: $0.01/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quietsignal-wallet-preflight-2142adef
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mzZFaDr2sjbiNomCDlupV

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 quietsignal-wallet-preflight-2142adef
```

Example prompt: Can you do a quick preflight check on the wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 to see if it has any native ETH or stablecoin balance on Base?

## When to prefer this

Choose this endpoint when an agent needs a fast, cheap ($0.01 USDC) read-only signal about whether a Base network wallet holds any native or stablecoin assets — particularly useful as a preflight step before initiating transactions, filtering wallets in bulk pipelines, or validating addresses prior to DeFi interactions. Prefer this over a full on-chain RPC call when you want a structured, schema-versioned JSON response without managing RPC infrastructure.

## Known failure modes

- Missing or malformed 'address' query parameter returns a 400-level error
- Invalid EVM address format (not a 20-byte hex) likely returns a validation error
- Payment not supplied or insufficient USDC triggers HTTP 402 requiring x402 payment flow
- Address not found on Base returns false for both balance flags rather than an error
- Network unavailability or RPC issues may cause 5xx responses

## How this service works

QuietSignal Public Data: independent, read-only rollup, wallet, opportunity, and developer-data facts for agents, paid per request with USDC over HTTP 402 on Base.

## Output

Returns a JSON object conforming to the base-wallet-preflight/v1 schema, including the queried address, network identifier (eip155:8453 for Base), boolean flags for whether the wallet holds any native balance and any stablecoin balance, and a legal disclaimer noting the data is read-only public blockchain facts with no investment advice.

## 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",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "description": "Public 20-byte EVM address to inspect"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "schema": "base-wallet-preflight/v1",
  "address": "0x0000000000000000000000000000000000000000",
  "network": "eip155:8453",
  "disclaimer": "Read-only public blockchain facts; no signing, transfer, or investment advice.",
  "has_native_balance": false,
  "has_stablecoin_balance": false
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/quietsignal-wallet-preflight-2142adef/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 83-29-153-50.sslip.io](https://www.zero.xyz/host/83-29-153-50.sslip.io/llms.txt)