Check Prepaid Session Balance
sap_payments_prepaid_balanceFREE local tool that checks the remaining balance of a prepaid session. No x402 charge. Returns the session ID, remaining USD, total USD, per-call cost, expiry, and call count. Use this before calling sap_payments_call_paid_tool with prepaidSessionId to verify the session still has balance.
SAP MCP execution guidance: Intent: local non-custodial payment/signing bridge. Pricing: free; call directly without x402. Routing: local sap_payments bridge. It may sign x402 payment payloads or user-approved transactions locally, and must never expose keypair bytes. Signer boundary: user-controlled local profile or external signer; OOBE hosted MCP remains non-custodial.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| sessionId | No | Prepaid session ID returned by sap_payments_start_prepaid. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| totalUsd | Yes | Original USDC amount deposited when the session was created. | |
| callCount | Yes | Number of calls made using this session. | |
| expiresAt | Yes | ISO timestamp when the session expires. | |
| sessionId | Yes | The prepaid session ID checked. | |
| remainingUsd | Yes | Remaining USDC balance in the session. | |
| perCallCostUsd | Yes | Cost deducted per granted call. |