Changelog

All notable structural changes to the Transaction Authorization Protocol (TAP) are documented in this file.

This changelog focuses on:

  • New TAIPs and their acceptance status
  • Message format changes
  • Protocol structural changes
  • Breaking changes

[2025-09-05]

Enhanced

  • TAIP-14 Payment Requests: Enhanced supportedAssets field and composability integration
    • Enhanced supportedAssets field: Now supports both string and object formats for flexible pricing
      • String format: Simple asset identifiers for ~1:1 assets like stablecoins
      • Object format: Pricing objects with asset (CAIP-19, DTI, or ISO-4217), amount, and optional expires
      • Enables cross-currency payments (e.g., USD invoice accepting EUR at specific rate with IBAN settlement)
      • Supports volatile asset pricing (e.g., ETH, BTC) with precise amounts and rate expiration
    • Updated composability section: Replaced Transfer-based examples with Exchange/Quote pattern from TAIP-18
      • Shows proper use of Exchange requests for currency conversion in payment flows
      • Demonstrates parent-child relationship using pthid to link Exchange to Payment
      • Added TAIP-18 to requirements and references
    • Enhanced example demonstrates mixed payment methods: stablecoins, crypto with pricing, cross-currency fiat

[2025-09-01]

Added

  • TAIP-18 Asset Exchange: Added Exchange and Quote message types for cross-asset transactions
    • New Exchange message type for requesting asset conversion quotes (USDC to EURC, USD to crypto, cross-chain)
    • New Quote message type for liquidity provider responses with pricing and expiration timestamps
    • Support for multi-asset arrays enabling flexible routing and provider selection
    • Compatible with existing TAIP-4 Authorize/Settle flows for quote acceptance and settlement
    • Integration with TAIP-17 Escrow for counterparty risk management in exchanges
    • Enables use cases: cross-asset payments, FX transactions, on/off-ramp services, cross-chain bridging
    • Updated JSON Schemas: Added exchange.json and quote.json message schemas
    • Updated TypeScript Package v1.12.0: Added Exchange and Quote interfaces and message wrappers
    • Updated Documentation: Enhanced messages.md and transactions.md with Exchange and Quote documentation

[2025-08-23]

Enhanced

  • TAIP-15 Agent Connection Protocol: Enhanced transaction constraints for improved security and control
    • Added three new optional constraint fields to Connect messages:
      • allowedBeneficiaries - array of TAIP-6 Party objects for approved payment recipients
      • allowedSettlementAddresses - array of CAIP-10 addresses for approved settlement addresses
      • allowedAssets - array of CAIP-19 asset identifiers for approved transaction assets
    • Added comprehensive “Transaction Constraints” section explaining constraint purposes, enforcement requirements, and types
    • Updated transaction validation requirements to include new constraint checks
    • Enhanced test examples to demonstrate new constraint usage
    • Added CAIP-10 and CAIP-19 references for address and asset identifier standards
    • Updated JSON Schemas: Enhanced transaction-constraints.json schema to validate new constraint fields
    • Updated TypeScript Package v1.11.0: Enhanced TransactionConstraints interface and Zod validators

[2025-08-21]

Added

Changed

  • BREAKING: TAIP-15 Agent Connection Protocol: Major restructure to support multi-party connections
    • BREAKING: Replaced single agent field with required agents array following TAIP-3 pattern
    • BREAKING: Added required requester Party field to distinguish requesting party from principal
    • Agents array must include at least one agent with @id matching DIDComm from field and for attribute set to requester DID
    • Added “Parties and Agent Roles” section clarifying two-party connection model
    • Added support for AddAgents messages to dynamically add agents during connection flow
    • Updated all examples and diagrams to use Merchant/Customer/PSP Agent terminology
    • Updated JSON schemas, and test vectors to match new structure
    • Removed type attributes from all agent examples across codebase for consistency with TAIP-5 specification

Fixed

  • Agent Consistency: Updated TAIP-3 and TAIP-14 to require for attributes in agent arrays
    • Added specification requiring requesting agent (from DIDComm from field) to be included in agents array with proper for attribute
    • Updated all TAIP-3 examples to include for attributes mapping agents to the parties they represent
    • Updated TAIP-14 example to include merchant agent and proper for attributes
    • Ensures consistency with TAIP-15 and TAIP-17 agent array requirements
  • TypeScript Package v1.9.0: Released with TAIP-15 agent restructuring support
  • TypeScript Package v1.8.0: Released with enhanced DIDComm v2.1 support and new message types

[2025-08-18]

Added

  • TypeScript Package v1.7.0: Released enhanced TypeScript library with comprehensive documentation and fixes

[2025-08-16]

Fixed

  • Test Vector Issues: Fixed incorrect TAIP references and missing required fields in test vectors
    • Fixed authorization-required/valid-authorization-required.json to reference correct TAIP-4 instead of TAIP-15
    • Added required settlementAddress field to settle/valid.json test vector per TAIP-4 specification
  • Test Vector Organization: Reorganized test vector file structure for better maintainability
    • Moved top-level test vectors to appropriate subfolders based on message type
    • valid-authorize.json → authorize/ subfolder
    • valid-payment*.json → payment-request/ subfolder
    • valid-revert.json → revert/ subfolder
    • valid-settle.json → settle/ subfolder
    • Ensures consistent organization with existing test vector structure

[2025-08-13]

Changed

  • Test Vectors: Updated test vectors to reflect recent protocol changes
    • Updated AuthorizationRequired test vectors to reference TAIP-4 instead of TAIP-15
    • Added test vectors for TAIP-17 Escrow messages with valid and invalid examples
    • Added test vectors demonstrating PayTo URI support (RFC 8905) for traditional banking integration
    • Added examples for Transfer messages with IBAN PayTo URIs
    • Added Payment request examples with ACH/wire PayTo URIs

[2025-08-04]

Added

  • IVMS101 Data Inclusion Documentation: Explicitly documented existing capability for including IVMS101 identity data directly in party objects alongside schema.org data
    • Updated TAIP-6: Added explicit specification and examples for IVMS101 data in party objects
    • Added comprehensive examples showing Person and Organization with IVMS101 fields
    • Documented geographic addresses, national identifiers, and compliance data inclusion
    • Added privacy recommendations for selective disclosure of natural person information
    • Clarified that this capability was always supported by the JSON-LD extensibility but was not explicitly documented
  • TypeScript Package v1.6.0: Released enhanced TypeScript library with comprehensive documentation

Changed

  • TAIP-6 (Transaction Parties): Enhanced documentation to explicitly describe IVMS101 data inclusion
    • Documented that party objects can include both schema.org and IVMS101 properties
    • Added concrete examples for natural persons and organizations with compliance data
    • Added privacy recommendations for selective disclosure of sensitive information
    • Made explicit what was previously implicit through JSON-LD extensibility
  • TAIP-10 (IVMS101 Travel Rule): Updated to clarify dual approach for IVMS data exchange
    • Documented direct inclusion in party objects for transparent compliance
    • Maintained selective disclosure via presentations for enhanced privacy
    • Clarified that both approaches have always been supported for different use cases
  • TAIP-14 (Payments): Enhanced merchant examples to demonstrate IVMS101 compliance data
    • Updated examples to show both schema.org and IVMS101 properties
    • Demonstrated LEI codes, geographic addresses, and national identifiers for organizations
    • Added privacy considerations for natural person merchants

[2025-08-03]

Changed

  • AuthorizationRequired Message: Moved from TAIP-15 to TAIP-4 as standard authorization message
    • AuthorizationRequired is now part of the core transaction authorization protocol (TAIP-4)
    • Added optional from field to specify party type (customer, principal, originator) required to open URL
    • TAIP-15 now references TAIP-4 for complete AuthorizationRequired specification
    • Updated interface with enhanced documentation for both transaction and connection authorization
    • Added comprehensive test case example to TAIP-4
    • Updated messages.md to document AuthorizationRequired as part of authorization flow

[2025-07-28]

Added

  • RFC 8905 PayTo URI Support: Settlement addresses now support both blockchain (CAIP-10) and traditional payment systems (RFC 8905)
    • Added to TAIP-4: Authorize, Settle, and Revert messages now accept PayTo URIs for bank transfers
    • Added to TAIP-14: Payment messages support fallbackSettlementAddresses field
    • Added to Transfer, Capture, and Invoice messages
  • Fallback Settlement Addresses: New optional field in Payment messages for redundancy
    • Supports array of mixed CAIP-10 and RFC 8905 addresses
    • Enables failover mechanisms for fiat payments and crypto transfers
  • Purpose Code Types: Added ISO 20022 External Purpose Code union types
    • ExternalPurposeCode: 331 standardized purpose codes
    • ExternalCategoryPurposeCode: 48 category purpose codes
    • See packages/typescript/CHANGELOG.md for TypeScript implementation details
  • schema.org/Organization Attributes: Added optional organization metadata fields to Agents and Parties
    • Based on schema.org/Organization standard
    • Added fields: name, url, logo, description, email, telephone
    • Available for both Agent (TAIP-5) and Party (TAIP-6) entities
  • schema.org/Product Attributes: Added optional product metadata fields to Invoice Line Items
    • Based on schema.org/Product standard
    • Added fields to line items: name, image, url
    • Enhances invoice line items in TAIP-16 with richer product information

Changed

  • TypeScript Package (@taprsvp/types): Updated with RFC 8905 PayTo URI support, purpose code types, and schema.org attributes
  • JSON Schemas:
    • Created payto-uri.json and settlement-address.json common schemas
    • Updated all message schemas to support new settlement address formats
    • Fixed DIDComm message type pattern to match body @type format
    • Enhanced agent.json and party.json schemas with organization attributes
    • Updated invoice.json schema to include product attributes in line items

Updated

  • TAIP-4: Added RFC 8905 reference and examples for traditional payment settlement
  • TAIP-5: Added schema.org/Organization attributes to Agent specification
  • TAIP-6: Added schema.org/Organization attributes to Party specification
  • TAIP-14: Added fallbackSettlementAddresses field specification
  • TAIP-16: Added schema.org/Product attributes to invoice line items

[2025-06-25]

Changed

  • TAIP Status Updates:
    • TAIP-1: Transaction Authorization Improvement Proposals - Advanced to Final status
    • TAIPs 2-10 - Advanced to Last Call status:
      • TAIP-2: Messaging
      • TAIP-3: Virtual Asset Transfer
      • TAIP-4: Transaction Authorization Protocol
      • TAIP-5: Transaction Agents
      • TAIP-6: Transaction Parties
      • TAIP-7: Agent Policies
      • TAIP-8: Selective Disclosure
      • TAIP-9: Proof of Relationship
      • TAIP-10: IVMS101 for Travel Rule
    • TAIPs 15-16 - Advanced from Draft to Review status:
      • TAIP-15: Agent Connection Protocol
      • TAIP-16: Invoices

[2025-06-24]

Added

  • JSON Schema definitions for all TAP message types in /schemas/ directory
  • Developer resources page with implementation guides
  • TAIP-17: Composable Escrow workflow (Draft)
    • New Escrow message type for holding assets on behalf of parties
    • New Capture message type for releasing escrowed funds
    • Supports both cryptocurrency assets and fiat currency denominations
    • Enables payment guarantees and asset swap use cases
  • TypeScript Package: Added by field to Cancel interface

Removed

  • Complete message type (replaced by extended Authorize message)
  • Test vectors for removed Complete message

[2025-06-23]

Changed

  • BREAKING: Replaced Complete message with enhanced Authorize message to simplify flow
  • Made originator field optional in Transfer messages to support unknown originators
  • Made role field optional in Agent structures
  • Added principal as primary party in Connection messages

[2025-04-22]

Added

  • TAIP-16: Invoices - Structured invoice format for payment requests
  • MCC (Merchant Category Code) field to Party structure for merchant identification

[2025-03-31]

Added

  • expiry fields to Transfer, Authorize, and Connect messages for business intent expiration
  • Complete message for payment completion flows
  • amount field to Settle message for partial settlement support

Changed

  • Distinguished between message expiration (expires_time) and business expiration (expiry)

[2025-03-30]

Changed

  • BREAKING: Renamed PaymentRequest to Payment throughout codebase
  • Updated all references and test vectors

[2025-03-26]

Added

  • TAIP-15: Agent Connection Protocol - OAuth-style authorization flows for B2B integrations
  • Connect message for establishing agent connections
  • AuthorizationRequired message for connection approval flows

[2025-03-11]

Added

  • TAIP-13: Transaction Purpose Codes - ISO 20022 purpose code integration
  • Purpose and categoryPurpose fields to Transfer messages
  • PaymentRequest message (later renamed to Payment)

[2025-03-10]

Added

  • TAIP-14: Payment Requests - Merchant-initiated payment flows

[2025-03-07]

Added

  • Cancel message for transaction termination
  • Revert message for transaction reversal requests

[2025-03-05]

Added

  • TAIP-11: Legal Entity Identifier (LEI) - Institutional participant identification
  • TAIP-12: Hashed Participant Name Sharing - Privacy-preserving name matching
  • lei field to Party structure
  • nameHash field to Party structure

[2025-03-02]

Added

  • TAIP-10: IVMS101 for Travel Rule - Regulatory compliance integration
  • ivms101 field to Party structure for Travel Rule data

[2024-01-26]

Added

  • TAIP-9: Proof of Relationship - Agent-party relationship verification
  • ConfirmRelationship message
  • CACAO attachment support for DID proofs

[2024-01-25]

Added

  • TAIP-8: Selective Disclosure - Privacy-preserving credential sharing
  • RequirePresentation policy type
  • Presentation Exchange integration

[2024-01-24]

Added

  • TAIP-7: Agent Policies - Requirement enforcement framework
  • Policy structures: RequireAuthorization, RequirePresentation, RequirePurpose
  • UpdatePolicies message

[2024-01-23]

Added

  • TAIP-6: Transaction Parties - Party identification and representation
  • Party data structure with name, LEI, and verification methods

[2024-01-09]

Added

  • TAIP-3: Virtual Asset Transfer - Core transfer functionality
  • TAIP-4: Transaction Authorization Protocol - Core authorization flow
  • TAIP-5: Transaction Agents - Software agent framework
  • Transfer message for asset transfers
  • Authorization flow messages: Authorize, Settle, Reject
  • Agent management messages: UpdateAgent, AddAgents, ReplaceAgent, RemoveAgent
  • Agent data structure with roles and policies

[2023-12-19]

Added

  • TAIP-1: Transaction Authorization Improvement Proposals - Framework document

[2023-12-14]

Added

  • TAIP-2: Messaging - DIDComm v2 message format
  • Base message structure and threading model
  • JSON-LD context definitions
  • Initial repository structure

Message Type Summary

Current TAP Messages (19 total)

  1. Transfer - Virtual asset transfer initiation
  2. Payment - Payment request with invoice support
  3. Authorize - Transaction authorization (enhanced to replace Complete)
  4. Settle - On-chain settlement confirmation
  5. Reject - Transaction rejection
  6. Cancel - Transaction cancellation
  7. Revert - Transaction reversal request
  8. UpdateAgent - Agent information update
  9. UpdateParty - Party information update
  10. AddAgents - Add agents to transaction
  11. ReplaceAgent - Replace existing agent
  12. RemoveAgent - Remove agent from transaction
  13. ConfirmRelationship - Confirm party-agent relationship
  14. UpdatePolicies - Update agent policies
  15. Connect - Establish agent connection
  16. AuthorizationRequired - Request authorization (moved to TAIP-4)
  17. Escrow - Hold assets in escrow with conditions (TAIP-17)
  18. Capture - Release escrowed funds (TAIP-17)
  19. Presentation - Present verifiable credentials (TAIP-8)

Removed Messages

  • Complete (2024-06-12) - Functionality merged into Authorize message

Breaking Changes Summary

2024-06-12

  • Complete message removed - migrate to Authorize with settlement details
  • Cancel message now requires by field

2024-03-15

  • PaymentRequest renamed to Payment - update all message type references

2024-02-10

  • Transfer message supports optional originator - handle missing originator cases

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning for protocol versions.