feat(opencode): show actual model per turn

apps/mobile/src/features/threads/ThreadFeed.tsx

@@ -979,6 +979,15 @@ function renderFeedEntry(
         })}
         {showAssistantMeta ? (
           <View className="mt-1 flex-row items-center gap-1">
+            {message.actualModel ? (
+              <Text
+                accessibilityLabel={`Actual model: ${message.actualModel}`}
+                className="mr-1 max-w-[70%] font-t3-medium text-xs text-neutral-600 dark:text-neutral-400"
+                numberOfLines={1}
+              >
+                Model: {message.actualModel}
+              </Text>
+            ) : null}
             <CopyTextButton
               accessibilityLabel="Copy message"
               text={message.text}

apps/server/src/orchestration/Layers/ProjectionPipeline.ts

@@ -978,6 +978,11 @@ const makeOrchestrationProjectionPipeline = Effect.fn("makeOrchestrationProjecti
             turnId: event.payload.turnId,
             role: event.payload.role,
             text: nextText,
+            ...(event.payload.actualModel !== undefined
+              ? { actualModel: event.payload.actualModel }
+              : previousMessage?.actualModel !== undefined
+                ? { actualModel: previousMessage.actualModel }
+                : {}),
             ...(nextAttachments !== undefined ? { attachments: [...nextAttachments] } : {}),
             isStreaming: event.payload.streaming,
             createdAt: previousMessage?.createdAt ?? event.payload.createdAt,

apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts

@@ -25,6 +25,7 @@ import {
   ModelSelection,
   ProjectId,
   ThreadId,
+  TrimmedNonEmptyString,
 } from "@t3tools/contracts";
 import * as Arr from "effect/Array";
 import * as Effect from "effect/Effect";
@@ -82,6 +83,7 @@ const ProjectionProjectDbRowSchema = ProjectionProject.mapFields(
 const ProjectionThreadMessageDbRowSchema = ProjectionThreadMessage.mapFields(
   Struct.assign({
     isStreaming: Schema.Number,
+    actualModel: Schema.NullOr(TrimmedNonEmptyString),
     attachments: Schema.NullOr(Schema.fromJsonString(Schema.Array(ChatAttachment))),
   }),
 );
@@ -531,6 +533,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           turn_id AS "turnId",
           role,
           text,
+          actual_model AS "actualModel",
           attachments_json AS "attachments",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
@@ -974,6 +977,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           turn_id AS "turnId",
           role,
           text,
+          actual_model AS "actualModel",
           attachments_json AS "attachments",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
@@ -1217,6 +1221,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           turn_id AS "turnId",
           role,
           text,
+          actual_model AS "actualModel",
           attachments_json AS "attachments",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
@@ -1559,6 +1564,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                   id: row.messageId,
                   role: row.role,
                   text: row.text,
+                  ...(row.actualModel !== null ? { actualModel: row.actualModel } : {}),
                   ...(row.attachments !== null ? { attachments: row.attachments } : {}),
                   turnId: row.turnId,
                   streaming: row.isStreaming === 1,
@@ -2619,6 +2625,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
             id: row.messageId,
             role: row.role,
             text: row.text,
+            ...(row.actualModel !== null ? { actualModel: row.actualModel } : {}),
             turnId: row.turnId,
             streaming: row.isStreaming === 1,
             createdAt: row.createdAt,

apps/server/src/orchestration/Layers/ProviderRuntimeIngestion.test.ts

@@ -2621,6 +2621,72 @@ describe("ProviderRuntimeIngestion", () => {
     expect(completionEvents).toHaveLength(1);
   });
 
+  it("enriches an already completed assistant message with the actual turn model", async () => {
+    const harness = await createHarness();
+    const now = "2026-08-14T00:00:00.000Z";
+    const threadId = asThreadId("thread-1");
+    const turnId = asTurnId("turn-actual-model");
+    const itemId = asItemId("item-actual-model");
+
+    harness.emit({
+      type: "turn.started",
+      eventId: asEventId("evt-turn-started-actual-model"),
+      provider: ProviderDriverKind.make("opencode"),
+      createdAt: now,
+      threadId,
+      turnId,
+    });
+    await waitForThread(harness.readModel, (thread) => thread.session?.activeTurnId === turnId);
+
+    harness.emit({
+      type: "content.delta",
+      eventId: asEventId("evt-message-delta-actual-model"),
+      provider: ProviderDriverKind.make("opencode"),
+      createdAt: now,
+      threadId,
+      turnId,
+      itemId,
+      payload: { streamKind: "assistant_text", delta: "done" },
+    });
+    harness.emit({
+      type: "item.completed",
+      eventId: asEventId("evt-message-completed-actual-model"),
+      provider: ProviderDriverKind.make("opencode"),
+      createdAt: now,
+      threadId,
+      turnId,
+      itemId,
+      payload: { itemType: "assistant_message", status: "completed" },
+    });
+    await waitForThread(harness.readModel, (thread) =>
+      thread.messages.some(
+        (message) => message.id === "assistant:item-actual-model" && !message.streaming,
+      ),
+    );
+
+    harness.emit({
+      type: "turn.completed",
+      eventId: asEventId("evt-turn-completed-actual-model"),
+      provider: ProviderDriverKind.make("opencode"),
+      createdAt: now,
+      threadId,
+      turnId,
+      payload: { state: "completed", actualModel: "gpt-5.6-luna" },
+    });
+
+    const thread = await waitForThread(harness.readModel, (entry) =>
+      entry.messages.some(
+        (message) =>
+          message.id === "assistant:item-actual-model" && message.actualModel === "gpt-5.6-luna",
+      ),
+    );
+    const messages = thread.messages.filter(
+      (message) => message.id === "assistant:item-actual-model",
+    );
+    expect(messages).toHaveLength(1);
+    expect(messages[0]?.actualModel).toBe("gpt-5.6-luna");
+  });
+
   it("maps canonical request events into approval activities with requestKind", async () => {
     const harness = await createHarness();
     const now = "2026-01-01T00:00:00.000Z";

apps/server/src/orchestration/Layers/ProviderRuntimeIngestion.ts

@@ -1198,6 +1198,7 @@ const make = Effect.gen(function* () {
     finalDeltaCommandTag: string;
     fallbackText?: string;
     hasProjectedMessage?: boolean;
+    actualModel?: string;
   }) =>
     Effect.gen(function* () {
       const bufferedText = yield* takeBufferedAssistantText(input.messageId);
@@ -1228,6 +1229,7 @@ const make = Effect.gen(function* () {
           threadId: input.threadId,
           messageId: input.messageId,
           ...(input.turnId ? { turnId: input.turnId } : {}),
+          ...(input.actualModel ? { actualModel: input.actualModel } : {}),
           createdAt: input.createdAt,
         });
       }
@@ -1837,7 +1839,20 @@ const make = Effect.gen(function* () {
         const proposedPlans = detailedThread?.proposedPlans ?? [];
         const turnId = toTurnId(event.turnId);
         if (turnId) {
-          const assistantMessageIds = yield* getAssistantMessageIdsForTurn(thread.id, turnId);
+          const trackedAssistantMessageIds = yield* getAssistantMessageIdsForTurn(
+            thread.id,
+            turnId,
+          );
+          const completedAssistantMessageId = messages.findLast(
+            (message) => message.role === "assistant" && message.turnId === turnId,
+          )?.id;
+          const assistantMessageIds =
+            trackedAssistantMessageIds.size > 0
+              ? Array.from(trackedAssistantMessageIds)
+              : event.payload.actualModel && completedAssistantMessageId
+                ? [completedAssistantMessageId]
+                : [];
+          const terminalAssistantMessageId = assistantMessageIds.at(-1);
           yield* Effect.forEach(
             assistantMessageIds,
             (assistantMessageId) =>
@@ -1850,6 +1865,9 @@ const make = Effect.gen(function* () {
                 commandTag: "assistant-complete-finalize",
                 finalDeltaCommandTag: "assistant-delta-finalize-fallback",
                 hasProjectedMessage: findMessageById(messages, assistantMessageId) !== undefined,
+                ...(event.payload.actualModel && assistantMessageId === terminalAssistantMessageId
+                  ? { actualModel: event.payload.actualModel }
+                  : {}),
               }),
             { concurrency: 1 },
           ).pipe(Effect.asVoid);

apps/server/src/orchestration/decider.ts

@@ -1271,6 +1271,7 @@ export const decideOrchestrationCommand = Effect.fn("decideOrchestrationCommand"
           messageId: command.messageId,
           role: "assistant",
           text: "",
+          ...(command.actualModel ? { actualModel: command.actualModel } : {}),
           turnId: command.turnId ?? null,
           streaming: false,
           createdAt: command.createdAt,

apps/server/src/orchestration/projector.ts

@@ -507,6 +507,7 @@ export function projectEvent(
             id: payload.messageId,
             role: payload.role,
             text: payload.text,
+            ...(payload.actualModel !== undefined ? { actualModel: payload.actualModel } : {}),
             ...(payload.attachments !== undefined ? { attachments: payload.attachments } : {}),
             turnId: payload.turnId,
             streaming: payload.streaming,
@@ -531,6 +532,9 @@ export function projectEvent(
                     streaming: message.streaming,
                     updatedAt: message.updatedAt,
                     turnId: message.turnId,
+                    ...(message.actualModel !== undefined
+                      ? { actualModel: message.actualModel }
+                      : {}),
                     ...(message.attachments !== undefined
                       ? { attachments: message.attachments }
                       : {}),

apps/server/src/persistence/Layers/ProjectionThreadMessages.test.ts

@@ -12,6 +12,43 @@ const layer = it.layer(
 );
 
 layer("ProjectionThreadMessageRepository", (it) => {
+  it.effect("persists actual model metadata across later partial upserts", () =>
+    Effect.gen(function* () {
+      const repository = yield* ProjectionThreadMessageRepository;
+      const threadId = ThreadId.make("thread-actual-model");
+      const messageId = MessageId.make("message-actual-model");
+      const createdAt = "2026-08-14T00:00:00.000Z";
+
+      yield* repository.upsert({
+        messageId,
+        threadId,
+        turnId: null,
+        role: "assistant",
+        text: "complete",
+        actualModel: "gpt-5.6-luna",
+        isStreaming: false,
+        createdAt,
+        updatedAt: createdAt,
+      });
+      yield* repository.upsert({
+        messageId,
+        threadId,
+        turnId: null,
+        role: "assistant",
+        text: "complete",
+        isStreaming: false,
+        createdAt,
+        updatedAt: "2026-08-14T00:00:01.000Z",
+      });
+
+      const row = yield* repository.getByMessageId({ messageId });
+      assert.equal(row._tag, "Some");
+      if (row._tag === "Some") {
+        assert.equal(row.value.actualModel, "gpt-5.6-luna");
+      }
+    }),
+  );
+
   it.effect("preserves existing attachments when upsert omits attachments", () =>
     Effect.gen(function* () {
       const repository = yield* ProjectionThreadMessageRepository;

apps/server/src/persistence/Layers/ProjectionThreadMessages.ts

@@ -5,7 +5,7 @@ import * as Layer from "effect/Layer";
 import * as Option from "effect/Option";
 import * as Schema from "effect/Schema";
 import * as Struct from "effect/Struct";
-import { ChatAttachment } from "@t3tools/contracts";
+import { ChatAttachment, TrimmedNonEmptyString } from "@t3tools/contracts";
 
 import { toPersistenceSqlError } from "../Errors.ts";
 import {
@@ -20,6 +20,7 @@ import {
 const ProjectionThreadMessageDbRowSchema = ProjectionThreadMessage.mapFields(
   Struct.assign({
     isStreaming: Schema.Number,
+    actualModel: Schema.NullOr(TrimmedNonEmptyString),
     attachments: Schema.NullOr(Schema.fromJsonString(Schema.Array(ChatAttachment))),
   }),
 );
@@ -33,6 +34,7 @@ function toProjectionThreadMessage(
     turnId: row.turnId,
     role: row.role,
     text: row.text,
+    ...(row.actualModel !== null ? { actualModel: row.actualModel } : {}),
     isStreaming: row.isStreaming === 1,
     createdAt: row.createdAt,
     updatedAt: row.updatedAt,
@@ -55,6 +57,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           turn_id,
           role,
           text,
+          actual_model,
           attachments_json,
           is_streaming,
           created_at,
@@ -66,6 +69,14 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           ${row.turnId},
           ${row.role},
           ${row.text},
+          COALESCE(
+            ${row.actualModel ?? null},
+            (
+              SELECT actual_model
+              FROM projection_thread_messages
+              WHERE message_id = ${row.messageId}
+            )
+          ),
           COALESCE(
             ${nextAttachmentsJson},
             (
@@ -84,6 +95,10 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           turn_id = excluded.turn_id,
           role = excluded.role,
           text = excluded.text,
+          actual_model = COALESCE(
+            excluded.actual_model,
+            projection_thread_messages.actual_model
+          ),
           attachments_json = COALESCE(
             excluded.attachments_json,
             projection_thread_messages.attachments_json
@@ -106,6 +121,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           turn_id AS "turnId",
           role,
           text,
+          actual_model AS "actualModel",
           attachments_json AS "attachments",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
@@ -127,6 +143,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           turn_id AS "turnId",
           role,
           text,
+          actual_model AS "actualModel",
           attachments_json AS "attachments",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",

apps/server/src/persistence/Migrations.ts

@@ -53,6 +53,7 @@ import Migration0037 from "./Migrations/037_ProjectionTurnsKeysetIndex.ts";
 import Migration0038 from "./Migrations/038_ProjectionThreadsPinOrderKey.ts";
 import Migration0039 from "./Migrations/039_ProjectionProjectsDefaultThreadEnvMode.ts";
 import Migration0040 from "./Migrations/040_ProjectionProjectFaviconPath.ts";
+import Migration0041 from "./Migrations/041_ProjectionThreadMessageActualModel.ts";
 
 /**
  * Migration loader with all migrations defined inline.
@@ -105,6 +106,7 @@ export const migrationEntries = [
   [38, "ProjectionThreadsPinOrderKey", Migration0038],
   [39, "ProjectionProjectsDefaultThreadEnvMode", Migration0039],
   [40, "ProjectionProjectFaviconPath", Migration0040],
+  [41, "ProjectionThreadMessageActualModel", Migration0041],
 ] as const;
 
 export const migrationManifest = migrationEntries.map(([id, name]) => [id, name] as const);

apps/server/src/persistence/Migrations/041_ProjectionThreadMessageActualModel.test.ts

@@ -0,0 +1,28 @@
+import { assert, it } from "@effect/vitest";
+import * as Effect from "effect/Effect";
+import * as Layer from "effect/Layer";
+import * as SqlClient from "effect/unstable/sql/SqlClient";
+
+import { runMigrations } from "../Migrations.ts";
+import * as NodeSqliteClient from "../NodeSqliteClient.ts";
+
+const layer = it.layer(Layer.mergeAll(NodeSqliteClient.layerMemory()));
+
+layer("041_ProjectionThreadMessageActualModel", (it) => {
+  it.effect("adds the nullable actual model to message projections", () =>
+    Effect.gen(function* () {
+      const sql = yield* SqlClient.SqlClient;
+
+      yield* runMigrations({ toMigrationInclusive: 40 });
+      yield* runMigrations({ toMigrationInclusive: 41 });
+
+      const columns = yield* sql<{ readonly name: string; readonly notnull: number }>`
+        PRAGMA table_info(projection_thread_messages)
+      `;
+      const actualModel = columns.find((column) => column.name === "actual_model");
+
+      assert.equal(actualModel?.name, "actual_model");
+      assert.equal(actualModel?.notnull, 0);
+    }),
+  );
+});