fix: use type from the reply nested content directly

packages/content-type-reply/src/Reply.ts

@@ -28,10 +28,6 @@ export type Reply = {
   contentType: ContentTypeId;
 };
 
-export type ReplyParameters = Pick<Reply, "reference"> & {
-  contentType: string;
-};
-
 export class ReplyCodec implements ContentCodec<Reply> {
   get contentType(): ContentTypeId {
     return ContentTypeReply;
@@ -40,7 +36,7 @@ export class ReplyCodec implements ContentCodec<Reply> {
   encode(
     content: Reply,
     codecs: CodecRegistry,
-  ): EncodedContent<ReplyParameters> {
+  ): EncodedContent {
     const codec = codecs.codecFor(content.contentType);
     if (!codec) {
       throw new Error(
@@ -54,6 +50,7 @@ export class ReplyCodec implements ContentCodec<Reply> {
     return {
       type: ContentTypeReply,
       parameters: {
+        // TODO: cut when we're certain no one is looking for "contentType" here.
         contentType: content.contentType.toString(),
         reference: content.reference,
       },
@@ -62,18 +59,16 @@ export class ReplyCodec implements ContentCodec<Reply> {
   }
 
   decode(
-    content: EncodedContent<ReplyParameters>,
+    content: EncodedContent,
     codecs: CodecRegistry,
   ): Reply {
     const decodedContent = proto.EncodedContent.decode(content.content);
-    const contentType = ContentTypeId.fromString(
-      content.parameters.contentType,
-    );
+    const contentType = decodedContent.type;
 
     const codec = codecs.codecFor(contentType);
     if (!codec) {
       throw new Error(
-        `missing codec for content type "${content.parameters.contentType}"`,
+        `missing codec for content type "${contentType.toString()}"`,
       );
     }
 

packages/content-type-reply/src/index.ts

@@ -1,2 +1,2 @@
 export { ReplyCodec, ContentTypeReply } from "./Reply";
-export type { Reply, ReplyParameters } from "./Reply";
+export type { Reply } from "./Reply";