Reference-grade decode and lookup tools for payment professionals. ISO 8583 message decoding, payment return code lookup, LEI/BIC/IBAN decoding, regulatory acronym reference, SWIFT MT→MX field migration mapping, payment error code resolution, and MCC code exploration — all browser-based, no accounts, zero data transmitted.
Seven standalone browser tools covering every major payment reference and decode need — from raw ISO 8583 message parsing to SWIFT migration mapping, identifier validation, and MCC lookup. All tools run in your browser with no account required.
Decodes ISO 8583 payment message fields (DE1–DE128) with data element definitions, format types, length attributes, and presence indicators. Covers all major versions (1987, 1993, 2003) and financial transaction message classes.
Open ToolComprehensive library of payment return and rejection codes across SWIFT, SEPA, ACH, and card networks. Look up return reason, category, network origin, and remediation guidance for any rejection code.
Open ToolResolves payment decline and error codes across SWIFT, SEPA, NACHA ACH, Visa, and Mastercard rails with root cause analysis, responsible party identification, and step-by-step remediation steps.
Open ToolDecodes and validates Legal Entity Identifiers (ISO 17442), Bank Identifier Codes (ISO 9362), and International Bank Account Numbers (ISO 13616). Parses structure, extracts components, and flags format violations.
Open ToolLook up merchant category codes with interchange rate implications, restriction flags, industry classifications, and scheme-specific notes. Searchable across all ISO 18245 MCC codes used by Visa, Mastercard, Amex, and Discover.
Open ToolMaps legacy SWIFT MT message fields to their ISO 20022 MX equivalents with truncation risk alerts, data loss flags, and structured migration guidance. Covers MT 103/202/940/950 and key cross-border payment messages.
Open ToolSearchable reference of 200+ fintech and payments regulatory acronyms with full definitions, originating framework context, issuing authority, and cross-references to related standards and regulations.
Open Toolv1.0 · June 2026 · 7 tools · Category 27 · Payment Reference Library
Follow this end-to-end decode workflow when investigating a failed or rejected payment across any major rail.
Start with T403 to identify the rail, root cause, and responsible party before drilling into message-level detail.
Use T361 to parse DE1–DE128 fields from the raw message bitmap and inspect each data element in detail.
Run T363 to check that all financial identifiers in the message are structurally valid and correctly formatted.
Look up the full return reason definition, network category, and remediation guidance in T362.
If the message is a legacy MT format, use T402 to map fields to ISO 20022 MX equivalents and check truncation risks.
For card transactions, use MCC Code Explorer to check interchange implications and scheme restriction flags.
Use T367 Regulatory Acronym Reference to look up any standards abbreviations or regulatory terms encountered.
Decode ISO 8583 messages during integration testing, validate BIC/IBAN formats, and resolve error codes during incident triage.
Look up return and rejection codes across rails, identify root cause of payment failures, and resolve operational incidents efficiently.
Reference 200+ regulatory acronyms, decode identifier formats for compliance checks, and map MT fields for ISO 20022 migration assessments.
Explore MCC codes, interchange flags, and scheme-specific notes. Cross-reference Visa/Mastercard network rules with card decline code definitions.
Validate IBAN/BIC identifiers for correspondent banking, decode SWIFT MT messages, and map to ISO 20022 MX for cross-border operations.
Tools in this hub decode and reference the following payment standards and network specifications. Verify current scheme rule versions with your network certification team.
Financial transaction card-originated messages. Versions 1987, 1993, and 2003. DE1–DE128 data element definitions, bitmap parsing, and full message class coverage.
MT to MX field migration mapping. pacs.008, pacs.009, camt.053/054 message families. SWIFT GPI tracking fields. Truncation and data loss risk identification.
SEPA Credit Transfer and Direct Debit return reason codes (EPC rulebook). NACHA ACH return codes R01–R85, NOC codes, and dishonour rules under NACHA 2024 rules.
Card decline and error code libraries. MCC ISO 18245 classification, interchange category flags, scheme restriction codes, and network-specific reason code definitions.
Open T403 Payment Error Code Resolver and enter the error or decline code. The tool identifies the originating rail (SWIFT/SEPA/ACH/Visa/MC), maps the root cause, and provides step-by-step remediation.
For card transactions use T361 ISO 8583 Message Decoder to parse raw DE fields. For SWIFT messages use T402 MT→MX Field Migration Decoder. Validate all identifiers with T363 LEI/BIC/IBAN Decoder.
Use T362 Return Code Library for cross-rail return reason definitions. Use T367 Acronym Reference for any unfamiliar regulatory terms. Look up card MCC codes with the MCC Code Explorer.
All 7 tools expose structured outputs compatible with the AINumbers MCP manifest.
| Tool ID | MCP Name | Input Schema | Output |
|---|---|---|---|
| T361 | decode_iso8583_message | raw_message_hex, iso_version, message_class | parsed_fields{}, bitmap_map{}, element_definitions[] |
| T362 | lookup_payment_return_code | return_code, network_rail, message_type | reason_definition, category, network, remediation_steps[] |
| T363 | decode_validate_payment_identifier | identifier, identifier_type | parsed_components{}, validation_result, format_flags[] |
| T367 | lookup_regulatory_acronym | acronym, context_domain | definition, framework_context, issuing_authority, cross_refs[] |
| MCC | lookup_mcc_code | mcc_code, network | description, industry_group, interchange_category, restriction_flags[] |
| T402 | map_swift_mt_to_mx_fields | mt_message_type, field_tags[], content_sample | mx_mapping{}, truncation_risks[], migration_notes[] |
| T403 | resolve_payment_error_code | error_code, originating_rail, transaction_type | root_cause, responsible_party, remediation_steps[], severity |