core: persist v2 assistant execution metadata

Author: thdxr

packages/opencode/src/session/processor.ts

@@ -437,6 +437,7 @@ export const layer: Layer.Layer<
             SyncEvent.run(SessionEvent.Step.Started.Sync, {
               id: SessionEvent.ID.create(),
               sessionID: ctx.sessionID,
+              agent: input.assistantMessage.agent,
               model: {
                 id: ctx.model.id,
                 providerID: ctx.model.providerID,
@@ -464,7 +465,7 @@ export const layer: Layer.Layer<
             // TODO(v2): Temporary dual-write while migrating session messages to v2 events.
             SyncEvent.run(SessionEvent.Step.Ended.Sync, {
               sessionID: ctx.sessionID,
-              reason: value.finishReason,
+              finish: value.finishReason,
               cost: usage.cost,
               tokens: usage.tokens,
               snapshot: completedSnapshot,

packages/opencode/src/v2/session-event.ts

@@ -52,6 +52,7 @@ export namespace Step {
     schema: {
       ...Base,
       id: ID,
+      agent: Schema.String,
       model: Schema.Struct({
         id: Schema.String,
         providerID: Schema.String,
@@ -67,7 +68,7 @@ export namespace Step {
     aggregate: "sessionID",
     schema: {
       ...Base,
-      reason: Schema.String,
+      finish: Schema.String,
       cost: Schema.Number,
       tokens: Schema.Struct({
         input: Schema.Number,

packages/opencode/src/v2/session-message-updater.ts

@@ -82,6 +82,7 @@ export function update<Result>(adapter: Adapter<Result>, event: SessionEvent.Eve
         adapter.updateAssistant(
           produce(currentAssistant, (draft) => {
             draft.time.completed = event.data.timestamp
+            draft.finish = event.data.finish
             draft.cost = event.data.cost
             draft.tokens = event.data.tokens
             if (event.data.snapshot) draft.snapshot = { ...draft.snapshot, end: event.data.snapshot }

packages/opencode/src/v2/session-message.ts

@@ -123,11 +123,14 @@ export type AssistantContent = Schema.Schema.Type<typeof AssistantContent>
 export class Assistant extends Schema.Class<Assistant>("Session.Message.Assistant")({
   ...Base,
   type: Schema.Literal("assistant"),
+  agent: Schema.String,
+  model: SessionEvent.Step.Started.fields.data.fields.model,
   content: AssistantContent.pipe(Schema.Array),
   snapshot: Schema.Struct({
     start: Schema.String.pipe(Schema.optional),
     end: Schema.String.pipe(Schema.optional),
   }).pipe(Schema.optional),
+  finish: Schema.String.pipe(Schema.optional),
   cost: Schema.Number.pipe(Schema.optional),
   tokens: Schema.Struct({
     input: Schema.Number,
@@ -148,6 +151,8 @@ export class Assistant extends Schema.Class<Assistant>("Session.Message.Assistan
     return new Assistant({
       id: event.data.id,
       type: "assistant",
+      agent: event.data.agent,
+      model: event.data.model,
       time: {
         created: event.data.timestamp,
       },

packages/opencode/test/server/httpapi-session.test.ts

@@ -175,6 +175,8 @@ describe("session HttpApi", () => {
               const message = new SessionMessage.Assistant({
                 id: SessionMessage.ID.create(),
                 type: "assistant",
+                agent: "build",
+                model: { id: "model", providerID: "provider" },
                 time: { created: DateTime.makeUnsafe(1) },
                 content: [],
               })
@@ -189,6 +191,8 @@ describe("session HttpApi", () => {
                       time_created: 1,
                       data: {
                         time: { created: 1 },
+                        agent: message.agent,
+                        model: message.model,
                         content: message.content,
                       } as NonNullable<typeof SessionMessageTable.$inferInsert["data"]>,
                     },

packages/opencode/test/v2/session-message-updater.test.ts

@@ -14,6 +14,7 @@ test("step snapshots carry over to assistant messages", () => {
       id: SessionEvent.ID.create(),
       sessionID,
       timestamp: DateTime.makeUnsafe(1),
+      agent: "build",
       model: { id: "model", providerID: "provider" },
       snapshot: "before",
     },
@@ -24,7 +25,7 @@ test("step snapshots carry over to assistant messages", () => {
     data: {
       sessionID,
       timestamp: DateTime.makeUnsafe(2),
-      reason: "stop",
+      finish: "stop",
       cost: 0,
       tokens: {
         input: 1,
@@ -39,6 +40,7 @@ test("step snapshots carry over to assistant messages", () => {
   expect(state.messages[0]?.type).toBe("assistant")
   if (state.messages[0]?.type !== "assistant") return
   expect(state.messages[0].snapshot).toEqual({ start: "before", end: "after" })
+  expect(state.messages[0].finish).toBe("stop")
 })
 
 test("text ended populates assistant text content", () => {
@@ -51,6 +53,7 @@ test("text ended populates assistant text content", () => {
       id: SessionEvent.ID.create(),
       sessionID,
       timestamp: DateTime.makeUnsafe(1),
+      agent: "build",
       model: { id: "model", providerID: "provider" },
     },
   } satisfies SessionEvent.Event)