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@@ -1,3 +1,7 @@
+:submission-api-1_3_0: https://docs.fitko.de/fit-connect/docs/apis/submission-api?version=1.3.0
+:issues: https://git.fitko.de/fit-connect/planning/-/issues
+:official-docs: https://docs.fitko.de/fit-connect/docs/[official FIT-Connect documentation]
+
 [comment]
 --
 Types of changes:
@@ -18,8 +22,56 @@ Don't forget to tag @ https://git.fitko.de/fit-connect/submission-api/-/tags
 * The format is based on https://keepachangelog.com/en/1.1.0/[Keep a Changelog], and this project adheres to https://semver.org/spec/v2.0.0.html[Semantic Versioning].
 * If available, include a ticket number in format `(planning#XXXX)`.
 
-=== Unreleased
+=== [Unreleased] - YYYY-MM-DD
+
+=== [1.3.0] - 2024-01-08
+
+==== Added
+* The Submission API now has a new case management section since the bidirectional communication feature
+  adds more focus on cases. {issues}/460[(planning#460)]
+
+* The Submission API grew by two endpoints to retrieve a case / list all cases {issues}/460[(planning#460)]:
+  ** {submission-api-1_3_0}#get-/v1/cases/-caseId-[`http get /v1/cases/<caseId>`]
+  ** {submission-api-1_3_0}#get-/v1/cases[`http get /v1/cases`]
+
+* The Submission API grew by several endpoints to manage / create / handle replies, a new top-level entity {issues}/460[(planning#460)]:
+  ** {submission-api-1_3_0}#get-/v1/replies[`http get /v1/replies`] to list replies
+  ** {submission-api-1_3_0}#post-/v1/replies[`http post /v1/replies`] to create a reply
+  ** {submission-api-1_3_0}#get-/v1/replies/-replyId-[`http get /v1/replies/<replyId>`] to get a specific reply
+  ** {submission-api-1_3_0}#put-/v1/replies/-replyId-[`http put /v1/replies/<replyId>`] to submit a reply
+  ** {submission-api-1_3_0}#put-/v1/replies/-replyId-/accept[`http put /v1/replies/<replyId>/accept`] to accept a reply (as an online service)
+  ** {submission-api-1_3_0}#put-/v1/replies/-replyId-/reject[`http put /v1/replies/<replyId>/reject`] to reject a reply (as an online service)
+  ** {submission-api-1_3_0}#get-/v1/replies/-replyId-/attachments/-attachmentId-[`http get /v1/replies/<replyId>/attachments/<attachmentId>`] to get a reply attachment
+  ** {submission-api-1_3_0}#put-/v1/replies/-replyId-/attachments/-attachmentId-[`http put /v1/replies/<replyId>/attachments/<attachmentId>`] to upload a reply attachment
+
+* Similar to the {submission-api-1_3_0}#post-/v1/destinations[NewSubmissions callback],
+  the Submission API now has a {submission-api-1_3_0}#post-/v1/submissions[NewReplies callback] that gets called
+  every time a new reply is added to a case. {issues}/460[(planning#460)]
+
+* To enable bidirectional communication, an additional reply channel was added: `fitConnect`.
+  If a {submission-api-1_3_0}#post-/v1/destinations[destination supports] the `fitConnect` reply channel,
+  an https://docs.fitko.de/fit-connect/docs/metadata/overview/[online service may select it via the Metadata `replyChannel -> fitConnect`].
+  For more details, check the {official-docs}. {issues}/460[(planning#460)]
+
+==== Changed
+
+* The Submission API now uses https://spec.openapis.org/oas/v3.1.0[OpenAPI 3.1.0].
+
+* Consolidated Attachment and CreateAttachment entities to a common type JWE.
+  This might be relevant for code generation tools.
+  The content stays the same though.
+
+* Updated lots of descriptions and examples.
+  If you find more errors, please report them to https://gitlab.opencode.de/fitko/feedback/-/issues[OpenCode].
+
+* The {submission-api-1_3_0}#post-/v1/destinations[NewEvents callback] may now include
+  a list of replies in the field `replies`. {issues}/460[(planning#460)]
 
 ==== Fixed
 
-* fix: only clients with CORS requests get CORS headers (planning#501)
\ No newline at end of file
+* Only CORS requests receive CORS headers. {issues}/501[(planning#501)]
+
+=== [1.2.1] - 2023-08-09
+
+* Baseline changelog.
+  Check GIT history for a changelog of this and earlier versions.