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

# Buyer and agent — discover and pay

# Buyer and agent path

Instantiate `StellarBazaarClient`, call `search()` with a natural-language intent and optional network/type/payee filters, then call `paidCall()`. The first request obtains the canonical `PAYMENT-REQUIRED` challenge. Your wallet adapter receives the decoded challenge and must sign the Soroban authorization entry—not a pre-signed settlement transaction. The SDK retries with its returned `PAYMENT-SIGNATURE`.

Agents can use the MCP `search_services` and `paid_call` tools. Calling `paid_call` without a signature returns `paymentRequired` and `nextAction: SIGN_PAYMENT_AND_RETRY`; call it again with the wallet-created payload. Every MCP error includes `error.data.reason`.

Apply wallet policy before signing: network, settlement contract, asset, recipient, maximum per call, expiry, and aggregate budget. For `upto`, the on-chain cap is only the per-request ceiling; a smart account can enforce the broader session budget.