refactor: derive channel metadata from plugin manifests

src/utils/message-channel.test.ts

@@ -2,7 +2,10 @@ import { afterEach, beforeEach, describe, expect, it } from "vitest";
 import type { ChannelPlugin } from "../channels/plugins/types.js";
 import { setActivePluginRegistry } from "../plugins/runtime.js";
 import { createChannelTestPluginBase, createTestRegistry } from "../test-utils/channel-plugins.js";
-import { resolveGatewayMessageChannel } from "./message-channel.js";
+import {
+  isMarkdownCapableMessageChannel,
+  resolveGatewayMessageChannel,
+} from "./message-channel.js";
 
 const emptyRegistry = createTestRegistry([]);
 const demoAliasPlugin: ChannelPlugin = {
@@ -21,6 +24,15 @@ const demoAliasPlugin: ChannelPlugin = {
   },
 };
 
+const demoMarkdownPlugin: ChannelPlugin = {
+  ...createChannelTestPluginBase({
+    id: "demo-markdown-channel",
+    label: "Demo Markdown Channel",
+    docsPath: "/channels/demo-markdown-channel",
+    markdownCapable: true,
+  }),
+};
+
 describe("message-channel", () => {
   beforeEach(() => {
     setActivePluginRegistry(emptyRegistry);
@@ -45,4 +57,15 @@ describe("message-channel", () => {
     );
     expect(resolveGatewayMessageChannel("workspace-chat")).toBe("demo-alias-channel");
   });
+
+  it("reads markdown capability from channel metadata", () => {
+    expect(isMarkdownCapableMessageChannel("telegram")).toBe(true);
+    expect(isMarkdownCapableMessageChannel("whatsapp")).toBe(false);
+    setActivePluginRegistry(
+      createTestRegistry([
+        { pluginId: "demo-markdown-channel", plugin: demoMarkdownPlugin, source: "test" },
+      ]),
+    );
+    expect(isMarkdownCapableMessageChannel("demo-markdown-channel")).toBe(true);
+  });
 });

src/utils/message-channel.ts

@@ -1,6 +1,8 @@
 import type { ChannelId } from "../channels/plugins/types.js";
 import {
   CHANNEL_IDS,
+  getChatChannelMeta,
+  getRegisteredChannelPluginMeta,
   listRegisteredChannelPluginAliases,
   listRegisteredChannelPluginIds,
   listChatChannelAliases,
@@ -19,16 +21,6 @@ import {
 export const INTERNAL_MESSAGE_CHANNEL = "webchat" as const;
 export type InternalMessageChannel = typeof INTERNAL_MESSAGE_CHANNEL;
 
-const MARKDOWN_CAPABLE_CHANNELS = new Set<string>([
-  "slack",
-  "telegram",
-  "signal",
-  "discord",
-  "googlechat",
-  "tui",
-  INTERNAL_MESSAGE_CHANNEL,
-]);
-
 export { GATEWAY_CLIENT_NAMES, GATEWAY_CLIENT_MODES };
 export type { GatewayClientName, GatewayClientMode };
 export { normalizeGatewayClientName, normalizeGatewayClientMode };
@@ -139,5 +131,12 @@ export function isMarkdownCapableMessageChannel(raw?: string | null): boolean {
   if (!channel) {
     return false;
   }
-  return MARKDOWN_CAPABLE_CHANNELS.has(channel);
+  if (channel === INTERNAL_MESSAGE_CHANNEL || channel === "tui") {
+    return true;
+  }
+  const builtInChannel = normalizeChatChannelId(channel);
+  if (builtInChannel) {
+    return getChatChannelMeta(builtInChannel).markdownCapable === true;
+  }
+  return getRegisteredChannelPluginMeta(channel)?.markdownCapable === true;
 }