feat(session): add turn diff route

packages/client/src/effect/api/api.ts

@@ -17,6 +17,7 @@ import type { PromptInput } from "@opencode-ai/schema/prompt-input"
 import type { AgentAttachment } from "@opencode-ai/schema/prompt"
 import type { Skill } from "@opencode-ai/schema/skill"
 import type { Event } from "@opencode-ai/schema/event"
+import type { FileDiff } from "@opencode-ai/schema/file-diff"
 import type { InstructionEntry } from "@opencode-ai/schema/instruction-entry"
 import type { Schema } from "effect"
 import type { EventLog } from "@opencode-ai/schema/event-log"
@@ -36,7 +37,6 @@ import type { PtyTicket } from "@opencode-ai/schema/pty-ticket"
 import type { Reference } from "@opencode-ai/schema/reference"
 import type { Worktree } from "@opencode-ai/schema/worktree"
 import type { Vcs } from "@opencode-ai/schema/vcs"
-import type { FileDiff } from "@opencode-ai/schema/file-diff"
 import type { WebSearch } from "@opencode-ai/schema/websearch"
 import type { Config } from "@opencode-ai/schema/config"
 
@@ -360,6 +360,15 @@ export type SessionContextInput = { readonly sessionID: Session.ID }
 export type SessionContextOutput = ReadonlyArray<SessionMessage.Info>
 export type SessionContextOperation<E = never> = (input: SessionContextInput) => Effect.Effect<SessionContextOutput, E>
 
+export type SessionDiffInput = {
+  readonly sessionID: Session.ID
+  readonly messageID?: SessionMessage.ID | undefined
+  readonly to?: SessionMessage.ID | undefined
+  readonly context?: number | undefined
+}
+export type SessionDiffOutput = ReadonlyArray<FileDiff.Info>
+export type SessionDiffOperation<E = never> = (input: SessionDiffInput) => Effect.Effect<SessionDiffOutput, E>
+
 export type SessionInboxListInput = { readonly sessionID: Session.ID }
 export type SessionInboxListOutput = ReadonlyArray<SessionInbox.Info>
 export type SessionInboxListOperation<E = never> = (
@@ -1133,6 +1142,7 @@ export interface SessionApi<E = never> {
     readonly commit: SessionRevertCommitOperation<E>
   }
   readonly context: SessionContextOperation<E>
+  readonly diff: SessionDiffOperation<E>
   readonly inbox: {
     readonly list: SessionInboxListOperation<E>
     readonly cancel: SessionInboxCancelOperation<E>

packages/client/src/effect/generated/client.ts

@@ -68,6 +68,8 @@ import type {
   SessionRevertCommitOutput,
   SessionContextInput,
   SessionContextOutput,
+  SessionDiffInput,
+  SessionDiffOutput,
   SessionInboxListInput,
   SessionInboxListOutput,
   SessionInboxCancelInput,
@@ -594,6 +596,17 @@ const EndpointSessionContext = (raw: RawClient["server.session"]) => (input: Ses
     ),
   )
 
+const EndpointSessionDiff = (raw: RawClient["server.session"]) => (input: SessionDiffInput) =>
+  preserveEffect<SessionDiffOutput>()(
+    raw["session.diff"]({
+      params: { sessionID: input["sessionID"] },
+      query: { messageID: input["messageID"], to: input["to"], context: input["context"] },
+    }).pipe(
+      Effect.mapError(mapClientError),
+      Effect.map((value) => value.data),
+    ),
+  )
+
 const EndpointSessionInboxList = (raw: RawClient["server.session"]) => (input: SessionInboxListInput) =>
   preserveEffect<SessionInboxListOutput>()(
     raw["session.inbox.list"]({ params: { sessionID: input["sessionID"] } }).pipe(
@@ -744,6 +757,7 @@ const adaptGroupSession = (raw: RawClient["server.session"]) => ({
     commit: EndpointSessionRevertCommit(raw),
   },
   context: EndpointSessionContext(raw),
+  diff: EndpointSessionDiff(raw),
   inbox: {
     list: EndpointSessionInboxList(raw),
     cancel: EndpointSessionInboxCancel(raw),

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

@@ -62,6 +62,8 @@ import type {
   SessionRevertCommitOutput,
   SessionContextInput,
   SessionContextOutput,
+  SessionDiffInput,
+  SessionDiffOutput,
   SessionInboxListInput,
   SessionInboxListOutput,
   SessionInboxCancelInput,
@@ -844,6 +846,18 @@ export function make(options: ClientOptions) {
           },
           requestOptions,
         ).then((value) => value.data),
+      diff: (input: SessionDiffInput, requestOptions?: RequestOptions) =>
+        request<{ readonly data: SessionDiffOutput }>(
+          {
+            method: "GET",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/diff`,
+            query: { messageID: input["messageID"], to: input["to"], context: input["context"] },
+            successStatus: 200,
+            declaredStatuses: [400, 401, 404, 500],
+            empty: false,
+          },
+          requestOptions,
+        ).then((value) => value.data),
       inbox: {
         list: (input: SessionInboxListInput, requestOptions?: RequestOptions) =>
           request<{ readonly data: SessionInboxListOutput }>(

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

@@ -147,6 +147,14 @@ export type SessionProviderContextProvenance = {
   endpoint: string
 }
 
+export type SessionMessageIdle = {
+  id: string
+  metadata?: { [x: string]: JsonValue }
+  time: { created: number }
+  type: "idle"
+  outcome: "succeeded" | "failed" | "interrupted"
+}
+
 export type SessionActive = { type: "running" }
 
 export type SessionInboxDelivery = "steer" | "queue"
@@ -2177,6 +2185,7 @@ export type SessionMessageInfo =
   | SessionMessageShell
   | SessionMessageAssistant
   | SessionMessageCompaction
+  | SessionMessageIdle
 
 export type SessionMessageContentUpdated = {
   id: string
@@ -3122,6 +3131,13 @@ export type SessionImportInput = {
               readonly error: { readonly type: string; readonly message: string; readonly status?: number }
             }
         )
+      | {
+          readonly id: string
+          readonly metadata?: { readonly [x: string]: JsonValue }
+          readonly time: { readonly created: number }
+          readonly type: "idle"
+          readonly outcome: "succeeded" | "failed" | "interrupted"
+        }
     >
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
   }["info"]
@@ -3413,6 +3429,13 @@ export type SessionImportInput = {
               readonly error: { readonly type: string; readonly message: string; readonly status?: number }
             }
         )
+      | {
+          readonly id: string
+          readonly metadata?: { readonly [x: string]: JsonValue }
+          readonly time: { readonly created: number }
+          readonly type: "idle"
+          readonly outcome: "succeeded" | "failed" | "interrupted"
+        }
     >
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
   }["messages"]
@@ -3704,6 +3727,13 @@ export type SessionImportInput = {
               readonly error: { readonly type: string; readonly message: string; readonly status?: number }
             }
         )
+      | {
+          readonly id: string
+          readonly metadata?: { readonly [x: string]: JsonValue }
+          readonly time: { readonly created: number }
+          readonly type: "idle"
+          readonly outcome: "succeeded" | "failed" | "interrupted"
+        }
     >
     readonly location?: { readonly directory: string; readonly workspaceID?: string } | null
   }["location"]
@@ -4193,6 +4223,27 @@ export type SessionContextInput = { readonly sessionID: { readonly sessionID: st
 
 export type SessionContextOutput = { data: Array<SessionMessageInfo> }["data"]
 
+export type SessionDiffInput = {
+  readonly sessionID: { readonly sessionID: string }["sessionID"]
+  readonly messageID?: {
+    readonly messageID?: string | undefined
+    readonly to?: string | undefined
+    readonly context?: number | undefined
+  }["messageID"]
+  readonly to?: {
+    readonly messageID?: string | undefined
+    readonly to?: string | undefined
+    readonly context?: number | undefined
+  }["to"]
+  readonly context?: {
+    readonly messageID?: string | undefined
+    readonly to?: string | undefined
+    readonly context?: number | undefined
+  }["context"]
+}
+
+export type SessionDiffOutput = { data: Array<FileDiffInfo> }["data"]
+
 export type SessionInboxListInput = { readonly sessionID: { readonly sessionID: string }["sessionID"] }
 
 export type SessionInboxListOutput = { data: Array<SessionInboxInfo> }["data"]

packages/client/src/solid/data.ts

@@ -1032,6 +1032,18 @@ export function createData(config: CreateDataInput) {
           if (currentAssistant) currentAssistant.retry = undefined
         })
         if (event.type === "session.execution.interrupted" && event.data.reason === "shutdown") return
+        // Mirror the projected idle marker so turn boundaries match before the next message read.
+        message.insert(event.data.sessionID, {
+          id: messageIDFromEvent(event.id),
+          type: "idle",
+          outcome:
+            event.type === "session.execution.succeeded"
+              ? "succeeded"
+              : event.type === "session.execution.failed"
+                ? "failed"
+                : "interrupted",
+          time: { created: event.created },
+        })
         // An event can overtake the first read; queue a revalidation when that read is still active.
         if (!store.session.info[event.data.sessionID] && !sync.has(`session:${event.data.sessionID}`)) return
         result.session.invalidate(event.data.sessionID)