Conversation API Release Notes

See how the Sinch Conversation API is evolving and find out about new features and bug fixes. Any notes labeled with a future date are included for preparatory reasons and are identified as such. Any breaking changes are listed under a corresponding Breaking changes sub-heading.

2025-04-16 (upcoming breaking change)

Breaking changes

• Beginning April 16th, 2025 , a breaking change will be introduced to the Conversation API. The default processing mode will change from CONVERSATION to DISPATCH .

  This change will impact all new Conversation API apps created after this date. Existing apps are unaffected by this upcoming change.

  Please review your configurations and update any dependencies accordingly.

2025-03-05

• Added support for channel_metadata in smart conversations callbacks
• Improved handling of callbacks to avoid duplication

2025-02-19

• Added support credit validation on API calls. See 403 Status under common error responses .

2024-09-25

• Added channel_metadata field to callbacks. See Callback Format .

2024-09-11

• Added support for correlation_id in Dispatch processing mode .

2024-08-21

• Added support for conversation_metadata in Dispatch processing mode .

2024-08-07

• Added forwarding of message_metadata in user messages with reply_to .

2024-07-24

• Infrastructure updates.
• Bug fixes and internal improvements.

2024-05-15

• Bug fixes and performance improvements

2024-05-06

• Batch API made available for open beta usage for EU and US regions
• Added partial batch handling capability with Asynchronous Error Handling to Batch API
• Added parameterisation support for channel_properties

2024-04-17

• Batch API made available for open beta testing for BR region
• Added partial batch handling capability with Asynchronous Error Handling
• Added parameterisation support for channel_properties

2024-04-03

• Added support for Reply To to the Viber BM channel
• Bug fixes and performance improvements

2024-03-21

• Added support for Flows Messages to the WhatsApp channel

2024-03-20

• Improved Reply To , increasing support time to 3 days
• Added support for Reply To to the Telegram channel

2024-02-21

• Bug fixes and performance improvements

2024-02-14

• Fixed update app request , making display_name field optional
• Added support for configurable message retry time and Delivery Report based fallback
• Bug fixes and performance improvements

2023-11-14

• Added channel field to the list messages request to enable filtering messages by channel
• Added active_channel field to the list conversation request to enable filtering conversation by its active channel
• Added new Smart Conversations powered Message Redaction Webhook Trigger. See Redacted Messages . Note that Smart Conversations is currently available for open beta testing.

2023-09-20

• Added callback_settings object with secret_for_overridden_callback_urls field to the create app request and update app request to enable callback verification in dynamic message delivery
• Added the conversation_metadata_update_strategy field to the send message request (similar to the query parameter in the conversation update request )

2023-09-04

• Added documentation for version 2 (V2) of the Templates API . Moving forward, V2 of the Templates API is the recommended version for template creation, configuration, and maintenance via API calls. Some updates include:
  • Strongly typed translations field content , allowing the user to define the message using the same JSON structure used to define messages in a send message request
  • Improved validation
  • The option to override the omni-channel template configuration with a channel-specific template (for channels on which channel-specific templates can be created) using the explicit_channel_omni_message field

2023-06-29

• Improved the consistency of how MO Contact deliveries (that is, when a subscriber shares a Contact record with the business) are handled. Rather than delivering the Contact as a stringified text message type, it is now delivered as a media message with a URL linking to a vCard. The vCard has a TTL of 7 days; you must retrieve the vCard from the URL within that time period.

2023-06-14

• Added the correlation_id field to send message request
• Improved the handling of template messages sent with multiple channels defined. The template will now be properly evaluated for each different channel send attempt.
• Changed the CardMessage title field to optional on the send message request

2023-05-16

• Added format description to the documentation for the ttl field of the send message request of the Conversation API

2023-05-10

• Stricter validation of the channels provided in the channel priority order field of a Send Message request . All channels provided in this field must be configured in the corresponding Conversation API app, or the request will be rejected.

2023-04-19

• Added Smart Conversations functionality to the Conversation API app configuration options available on the Sinch Customer Dashboard . This feature allows you to add artificially intelligent analysis to your Conversation API app. Note that Smart Conversations is currently available for open beta testing.

2023-03-22

• Improved list messages endpoint , with the addition of new parameters to allow filtering messages by channel identity and accept_time.

2023-03-08

• Extended the existing list contacts endpoint to enable the retrieval of contact information based on externalId or channel-identity.

2023-02-01

• Improved handling of failed Send Event (POST /v1/projects/{project_id}/events:send) requests
• Deprecated Opt-In and Opt-out endpoints. They now return mocked responses to maintain backwards compatibility with existing integrations

2023-01-25

• Contact channel identities duplication protection mechanism in Conversation Api.

2023-01-11

• Updated the limit of options for choice messages to 10

2022-12-17

• Removed Conversation API Opt-In and Opt-Out endpoint documentation

2022-10-05

• Added List and Get query generators to the Sinch Customer Dashboard to assist developers with early integration troubleshooting. These queries can be used to retrieve and display information regarding messages , conversations , and contacts .

2022-09-09

• Added Markdown support for the Telegram Bot channel

2022-08-26

• Improved Conversation API metadata documentation (callbacks, conversations)

2022-08-10

• Queue Prioritisation to support HIGH_PRIORITY messages
• App Cache improvements
• Autoscaling improvements

2022-07-29

• Removed manual channel webhook configuration step when configuring Telegram and LINE channels via API

2022-06-01

• Added a webhook for when a contact is updated
• Added field metadata_update_strategy to Conversation Update

2022-04-27

• Added field default_sender to MMSCredentials
• Added the injected flag to the message object
• Added restriction to callback queue length per application

2022-04-13

• Improved webhook url validation

2022-03-21

• Internal improvements

2022-03-02

• Improved validation of the request body

2022-02-21

• Updated Postman Collection
• Moved List Message documentation to the Messages tab in the API reference section

2022-02-09

• Release of Dispatch processing mode support Beta
• Support for SMS_MAX_NUMBER_OF_MESSAGE_PARTS channel property on SMS channel

2022-01-21

• Release of WeChat channel support Beta

2021-12-15

• Added Processing Mode documentation
• Improved descriptions of several APIs
• Added more information to unsupported callbacks webhook
• Added support to conversation MO metadata

2021-11-16

• Release of LINE channel support Beta

2021-10-28

• Improved Apple BC card message with rich link transcoding

2021-09-29

• Release of Apple Business Chat channel support Beta

2021-09-22

• Allow 4 digit short code senders for the MMS channel
• Correctly populate the ViberBM DR timestamp

2021-09-21

• Improved Instagram icebreaker, shop product referral and story reply callbacks with metadata

2021-09-08

• Added support for Instagram private replies feature

2021-09-06

• Added supporting for Telegram Card & Choice Messages

2021-08-11

• Improved validation of Location and Choice Messages for Facebook Messenger
• Bugfix for timestamps in Viber Business contact messages
• Improved Instagram setup process with Facebook login button

2021-07-28

• Facebook Media Messages now support image, audio, video and document types
• Improved error messages for MMS channel media validation
• Viber Bot channel user profile query support

2021-07-14

• Release of KakaoTalk channel support Beta
• Improvements in validating content for WhatsApp message requests
• Validation of phone number contact identities

2021-07-08

• Release of Telegram channel support Beta

2021-06-24

• Improvements in transcoding of CardMessage and CarouselMessage for Instagram channel

2021-06-23

• Improvements on MMS channel for handling choice responses and contact messages that contain media attachments
• Improvements in message request validation
• Enabled setting contact metadata in message request for newly created contacts
• Handling of Suspended state for WhatsApp bots

2021-06-09

• Bugfixes in the CardMessage text formatting on WhatsApp and Viber Business channels
• Improvements for WhatsApp channel error response mapping and forwarding
• Support for vCard .vcf files on MMS channel in MediaMessage and CardMessage
• Support for MMS STRICT VALIDATION channel property to validate MMS media message contents against best practices
• Support for contact based retention policy
• New feature in Contact Management: enables fetching user profile from channels (this first release only supports Facebook Messenger)

2021-06-02

• Release of Instagram channel support Beta

2021-05-26

• Bugfix for supporting RCS CardMessage without media
• Improvements in retention policy execution

2021-05-12

• Improved request body validation
• Support for SMS_SENDER channel property to populate originator on SMS channel
• Added support for sending and receiving documents on Viber Business Messaging
• Improved error response mapping and forwarding on Viber Business and SMS channels
• Bugfix for keeping card order in RCS CarouselMessages

2021-04-28

• Improvements in Viber Business Messaging transcoding with text formatting
• Various bugfixes

2021-04-14

• Added support for MMS
• Added validation of URLs in MT messages
• Added validation against duplicated callback triggers
• Handle ChoiceResponseMessages on Viber Bot that have no match in the choice tracking data
• Fixed prematurely closed HTTP connection exceptions for WhatsApp