> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dripstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Free Browsing ($0 Identity)

> Browse discovery routes with a zero-dollar wallet identity proof — no payment, no API key.

The free twins under `/api/v2/x402/…` let wallet callers browse discovery
data without paying: search, sources, companies, entities, ticker
autocomplete, the stock-picks quote, and wallet introspection.

Access is a **zero-dollar identity proof** — the wallet signs a message, no
funds move. Two ways to prove identity:

## SIGN-IN-WITH-X (x402 wallets)

1. Build a CAIP-122 Sign-In-With-X message for this origin (domain, URI,
   version `1`, fresh random `nonce`, `issuedAt`, chain `eip155:*` or
   `solana:*`).
2. Sign with the wallet key (EIP-191 for EVM, ed25519 for Solana).
3. Base64-encode the payload and send it in the `sign-in-with-x` header.

**Proofs are single-use** — sign a fresh message per request, keep `issuedAt`
within 5 minutes.

```bash theme={null}
curl "https://dripstack.com/api/v2/x402/search?q=AI%20capex" \
  -H "sign-in-with-x: <base64 SIGN-IN-WITH-X proof>"
```

## MPP zero-amount proof

A plain request returns a `402` with a zero-amount `WWW-Authenticate: Payment`
challenge. Answer it with an MPP `proof` credential instead of a payment.

## Errors

| Code | Meaning |
| - | - |
| `402` | No identity proof yet — sign and retry |
| `401 invalid_siwx` | Malformed or invalid proof — re-sign |
| `401 siwx_replayed` | Proof already used — sign a fresh one |
| `403 wallet_only` | Sent an API key / JWT — account credentials are not accepted here |
| `429 wallet_rate_limited` | Per-wallet rate limit — retry shortly |


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