fix(tui): render instruction updates as compact notices (#41900)

packages/client/src/promise/generated/types.ts

@@ -65,6 +65,7 @@ export type SessionMessageSystem = {
   time: { created: number }
   type: "system"
   text: string
+  description?: string
 }
 
 export type SessionMessageSkill = {
@@ -2611,6 +2612,7 @@ export type SessionImportInput = {
           readonly time: { readonly created: number }
           readonly type: "system"
           readonly text: string
+          readonly description?: string
         }
       | {
           readonly id: string
@@ -2877,6 +2879,7 @@ export type SessionImportInput = {
           readonly time: { readonly created: number }
           readonly type: "system"
           readonly text: string
+          readonly description?: string
         }
       | {
           readonly id: string
@@ -3143,6 +3146,7 @@ export type SessionImportInput = {
           readonly time: { readonly created: number }
           readonly type: "system"
           readonly text: string
+          readonly description?: string
         }
       | {
           readonly id: string

packages/core/src/session/message-updater.ts

@@ -125,6 +125,7 @@ export function update(adapter: Adapter, event: SessionEvent.DurableEvent) {
             id: SessionMessage.ID.fromEvent(event.id),
             type: "system",
             text: event.data.text,
+            description: `Instructions updated: ${Object.keys(event.data.delta).join(", ")}`,
             metadata: event.metadata,
             time: { created: event.created },
           }),

packages/schema/src/session-message.ts

@@ -91,7 +91,10 @@ export interface System extends Schema.Schema.Type<typeof System> {}
 export const System = Schema.Struct({
   ...Base,
   type: Schema.tag("system"),
+  /** The model-facing update text, frozen at emit time. */
   text: Schema.String,
+  /** A short human-readable summary for transcript display. */
+  description: Schema.String.pipe(optional),
 }).annotate({ identifier: "Session.Message.System" })
 
 export interface Skill extends Schema.Schema.Type<typeof Skill> {}

packages/tui/src/context/data.tsx

@@ -523,19 +523,16 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
           })
           break
         case "session.instructions.updated":
-          const instructions = event.metadata?.instructions
-          if (
-            typeof instructions === "object" &&
-            instructions !== null &&
-            "initial" in instructions &&
-            instructions.initial === true
-          )
-            break
+          // Mirror the projector: the initial baseline and empty-rendering deltas carry no text
+          // and produce no transcript message.
+          const updateText = event.data.text
+          if (updateText === undefined) break
           message.update(event.data.sessionID, (draft, index) => {
             message.append(draft, index, {
               id: messageIDFromEvent(event.id),
               type: "system",
-              text: `Instructions updated: ${Object.keys(event.data.delta).join(", ")}`,
+              text: updateText,
+              description: `Instructions updated: ${Object.keys(event.data.delta).join(", ")}`,
               metadata: event.metadata,
               time: { created: event.created },
             })

packages/tui/src/routes/session/index.tsx

@@ -1695,7 +1695,7 @@ function SessionNoticeMessageV2(props: { message: SessionMessageInfo }) {
   const state = () => stringValue(metadata()?.state)
   const actor = () => (source() === "shell" ? "Shell" : Locale.titlecase(stringValue(metadata()?.agent) ?? "Subagent"))
   const text = () => {
-    if (props.message.type === "system") return props.message.text
+    if (props.message.type === "system") return props.message.description ?? "Instructions updated"
     if (props.message.type === "synthetic") return props.message.description ?? ""
     return ""
   }

packages/tui/test/cli/tui/data.test.tsx

@@ -2901,14 +2901,26 @@ test("skips initial instruction state and projects later updates with their mess
         delta: { "core/date": "1".repeat(64) },
       },
     })
+    emitEvent(events, {
+      id: "evt_instructions_3",
+      created: 2,
+      type: "session.instructions.updated",
+      durable: durable("session-1", 2, 2),
+      data: {
+        sessionID: "session-1",
+        delta: { "core/date": "2".repeat(64) },
+        text: "The current date has changed.",
+      },
+    })
 
-    await wait(() => sync.session.message.list("session-1")?.some((message) => message.time.created === 1))
+    await wait(() => sync.session.message.list("session-1")?.some((message) => message.time.created === 2))
     expect(sync.session.message.list("session-1")).toHaveLength(1)
     expect(sync.session.message.list("session-1")?.[0]).toMatchObject({
-      id: SessionMessage.ID.fromEvent(Event.ID.make("evt_instructions_2")),
+      id: SessionMessage.ID.fromEvent(Event.ID.make("evt_instructions_3")),
       type: "system",
-      text: "Instructions updated: core/date",
-      time: { created: 1 },
+      text: "The current date has changed.",
+      description: "Instructions updated: core/date",
+      time: { created: 2 },
     })
   } finally {
     app.renderer.destroy()