Strong foundation with clear naming, comprehensive descriptions, and proper Zod schemas. All 5 tools follow verb_noun pattern (create_*, check_*, refund_*). Descriptions are detailed (150-250 chars) and include critical context about money-moving operations and non-idempotency. Input schemas are well-defined with types and descriptions for all parameters. Tool annotations correctly flag destructive/irreversible operations. Main gaps: output schema not documented (what fields does JazzCashResponse contain?), no pagination/batching patterns (not applicable here), and error handling could be more granular (currently catches all errors uniformly). Parameter descriptions are strong but could benefit from explicit format constraints (e.g., mobile_number regex pattern in description, not just '03XXXXXXXXX' example).

• Document JazzCashResponse schema in tool descriptions or a separate schema section. Include fields like pp_ResponseCode, pp_ResponseMessage, voucher_number (for create_voucher), and any transaction ID returned.
• Add regex patterns to parameter descriptions: mobile_number: '03XXXXXXXXX (11 digits, starts with 03)', cnic: '6 digits', txn_ref: 'alphanumeric, auto-generated if omitted'.
• Implement error classification: catch and categorize errors as 'retryable' (timeout, 5xx), 'user_fixable' (invalid mobile, insufficient balance), or 'fatal' (auth failure). Return structured error with category and recovery hint.
• Add optional dry_run parameter to create_payment, create_mobile_account_payment, create_voucher, and refund_payment. When true, validate inputs and return estimated outcome without committing the transaction.
• Document environment variable requirements in tool descriptions or server startup message. E.g., 'Requires JAZZCASH_MERCHANT_ID, JAZZCASH_PASSWORD, JAZZCASH_INTEGRITY_SALT from JazzCash merchant portal.'