Migrate to ACP SDK 0.28 API

package.json

@@ -61,10 +61,11 @@
     "vitest": "^4.0.10"
   },
   "dependencies": {
-    "@agentclientprotocol/sdk": "^0.25.1",
+    "@agentclientprotocol/sdk": "^0.28.1",
     "@openai/codex": "^0.141.0",
     "diff": "^8.0.3",
     "open": "^11.0.0",
-    "vscode-jsonrpc": "^8.2.1"
+    "vscode-jsonrpc": "^8.2.1",
+    "zod": "^4.0.0"
   }
 }

src/ACPSessionConnection.ts

@@ -1,21 +1,23 @@
 import * as acp from "@agentclientprotocol/sdk";
 import type {SessionNotification} from "@agentclientprotocol/sdk";
 
+export type AcpClientConnection = Pick<acp.AgentContext, "notify" | "request">;
+
 export class ACPSessionConnection {
-    private readonly connection: acp.AgentSideConnection;
+    private readonly connection: AcpClientConnection;
     readonly sessionId: string;
 
-    constructor(connection: acp.AgentSideConnection, sessionId: string) {
+    constructor(connection: AcpClientConnection, sessionId: string) {
         this.connection = connection;
         this.sessionId = sessionId;
     }
 
     async update(update: UpdateSessionEvent) {
-        await this.connection.sessionUpdate({
+        await this.connection.notify(acp.methods.client.session.update, {
             sessionId: this.sessionId,
             update: update
         });
     }
 }
 
-export type UpdateSessionEvent = SessionNotification["update"];
+export type UpdateSessionEvent = SessionNotification["update"];

src/AcpExtensions.ts

@@ -1,5 +1,5 @@
 import type {
-    ClientSideConnection,
+    ClientContext,
     LoadSessionResponse,
     NewSessionResponse,
     ResumeSessionResponse,
@@ -61,8 +61,8 @@ export type LegacySetSessionModelExtRequest = {
 }
 
 export async function legacySetSessionModel(
-    connection: Pick<ClientSideConnection, "extMethod">,
+    connection: Pick<ClientContext, "request">,
     params: LegacySetSessionModelRequest,
 ): Promise<LegacySetSessionModelResponse> {
-    return await connection.extMethod(LEGACY_SET_SESSION_MODEL_METHOD, params) as LegacySetSessionModelResponse;
+    return await connection.request<LegacySetSessionModelResponse, LegacySetSessionModelRequest>(LEGACY_SET_SESSION_MODEL_METHOD, params);
 }

src/CodexAcpServer.ts

@@ -6,7 +6,7 @@ import {CodexElicitationHandler} from "./CodexElicitationHandler";
 import {type CodexAuthRequest, getCodexAuthMethods} from "./CodexAuthMethod";
 import {CodexAcpClient, type SessionMetadata, type SessionMetadataWithThread} from "./CodexAcpClient";
 import type {McpStartupResult} from "./CodexAppServerClient";
-import {ACPSessionConnection, type UpdateSessionEvent} from "./ACPSessionConnection";
+import {ACPSessionConnection, type AcpClientConnection, type UpdateSessionEvent} from "./ACPSessionConnection";
 import type {InputModality, ReasoningEffort} from "./app-server";
 import type {
     Account,
@@ -102,15 +102,15 @@ interface ActivePrompt {
     complete: () => void;
 }
 
-export class CodexAcpServer implements acp.Agent {
+export class CodexAcpServer {
     private static readonly MODEL_NAME_TOKEN_OVERRIDES: Record<string, string> = {
         gpt: "GPT",
         mini: "Mini",
         codex: "Codex",
     };
 
     private readonly codexAcpClient: CodexAcpClient;
-    private readonly connection: acp.AgentSideConnection;
+    private readonly connection: AcpClientConnection;
     private readonly defaultAuthRequest: CodexAuthRequest | null;
     private readonly getExitCode: () => number | null;
     private readonly getRecentStderr: () => string;
@@ -127,7 +127,7 @@ export class CodexAcpServer implements acp.Agent {
     private readonly sessionOpenGenerations: Map<string, number>;
 
     constructor(
-        connection: acp.AgentSideConnection,
+        connection: AcpClientConnection,
         codexAcpClient: CodexAcpClient,
         defaultAuthRequest?: CodexAuthRequest,
         getExitCode?: () => number | null,
@@ -1110,7 +1110,7 @@ export class CodexAcpServer implements acp.Agent {
             : mcpStartup;
 
         for (const update of CodexEventHandler.createMcpStartupUpdates(filteredStartup)) {
-            await this.connection.sessionUpdate({
+            await this.connection.notify(acp.methods.client.session.update, {
                 sessionId,
                 update,
             });
@@ -1281,7 +1281,7 @@ export class CodexAcpServer implements acp.Agent {
                 await this.codexAcpClient.waitForSessionNotifications(params.sessionId);
                 if (commandResult.turnCompleted?.turn.status === "interrupted") {
                     if (!this.sessionIsClosing(params.sessionId) && this.sessions.has(params.sessionId)) {
-                        await this.connection.sessionUpdate({
+                        await this.connection.notify(acp.methods.client.session.update, {
                             sessionId: params.sessionId,
                             update: {
                                 sessionUpdate: "agent_message_chunk",
@@ -1382,7 +1382,7 @@ export class CodexAcpServer implements acp.Agent {
             // Check if turn was interrupted (cancelled)
             if (turnCompleted.turn.status === "interrupted") {
                 if (!this.sessionIsClosing(params.sessionId) && this.sessions.has(params.sessionId)) {
-                    await this.connection.sessionUpdate({
+                    await this.connection.notify(acp.methods.client.session.update, {
                         sessionId: params.sessionId,
                         update: {
                             sessionUpdate: "agent_message_chunk",

src/CodexApprovalHandler.ts

@@ -17,6 +17,7 @@ import type {
 import {logger} from "./Logger";
 import {stripShellPrefix} from "./CodexEventHandler";
 import {ApprovalOptionId} from "./ApprovalOptionId";
+import type {AcpClientConnection} from "./ACPSessionConnection";
 
 type CommandDecisionOption = {
     option: acp.PermissionOption;
@@ -43,11 +44,11 @@ function permissionOption(
 }
 
 export class CodexApprovalHandler implements ApprovalHandler {
-    private readonly connection: acp.AgentSideConnection;
+    private readonly connection: AcpClientConnection;
     private readonly sessionState: SessionState;
 
     constructor(
-        connection: acp.AgentSideConnection,
+        connection: AcpClientConnection,
         sessionState: SessionState
     ) {
         this.connection = connection;
@@ -60,7 +61,7 @@ export class CodexApprovalHandler implements ApprovalHandler {
         try {
             const sessionId = this.sessionState.sessionId;
             const acpRequest = this.buildCommandPermissionRequest(sessionId, params);
-            const response = await this.connection.requestPermission(acpRequest);
+            const response = await this.connection.request(acp.methods.client.session.requestPermission, acpRequest);
             return this.convertCommandResponse(params, response);
         } catch (error) {
             logger.error("Error requesting command execution permission", error);
@@ -74,7 +75,7 @@ export class CodexApprovalHandler implements ApprovalHandler {
         try {
             const sessionId = this.sessionState.sessionId;
             const acpRequest = this.buildFileChangePermissionRequest(sessionId, params);
-            const response = await this.connection.requestPermission(acpRequest);
+            const response = await this.connection.request(acp.methods.client.session.requestPermission, acpRequest);
             return this.convertFileChangeResponse(params, response);
         } catch (error) {
             logger.error("Error requesting file change permission", error);
@@ -88,7 +89,7 @@ export class CodexApprovalHandler implements ApprovalHandler {
         try {
             const sessionId = this.sessionState.sessionId;
             const acpRequest = this.buildPermissionsRequest(sessionId, params);
-            const response = await this.connection.requestPermission(acpRequest);
+            const response = await this.connection.request(acp.methods.client.session.requestPermission, acpRequest);
             return this.convertPermissionsResponse(params, response);
         } catch (error) {
             logger.error("Error requesting permissions", error);

src/CodexCommands.ts

@@ -1,6 +1,6 @@
 import type * as acp from "@agentclientprotocol/sdk";
-import type {AgentSideConnection, AvailableCommand} from "@agentclientprotocol/sdk";
-import {ACPSessionConnection} from "./ACPSessionConnection";
+import type {AvailableCommand} from "@agentclientprotocol/sdk";
+import {ACPSessionConnection, type AcpClientConnection} from "./ACPSessionConnection";
 import type {CodexAcpClient} from "./CodexAcpClient";
 import type {RateLimitSnapshot, ReviewTarget, SkillsListEntry, TurnCompletedNotification} from "./app-server/v2";
 import type {SessionState} from "./CodexAcpServer";
@@ -18,12 +18,12 @@ export type CommandHandleResult =
     | { handled: true, turnCompleted?: TurnCompletedNotification };
 
 export class CodexCommands {
-    private readonly connection: AgentSideConnection;
+    private readonly connection: AcpClientConnection;
     private readonly codexAcpClient: CodexAcpClient;
     private readonly runWithProcessCheck: <T>(operation: () => Promise<T>) => Promise<T>;
 
     constructor(
-        connection: AgentSideConnection,
+        connection: AcpClientConnection,
         codexAcpClient: CodexAcpClient,
         runWithProcessCheck: <T>(operation: () => Promise<T>) => Promise<T>
     ) {

src/CodexElicitationHandler.ts

@@ -10,6 +10,7 @@ import type {
 } from "./app-server/v2";
 import { logger } from "./Logger";
 import { McpApprovalOptionId } from "./McpApprovalOptionId";
+import type {AcpClientConnection} from "./ACPSessionConnection";
 
 // Standard elicitation options (non-tool-call approval).
 const ELICITATION_OPTIONS: acp.PermissionOption[] = [
@@ -66,7 +67,7 @@ function buildToolApprovalOptions(persistOptions: Set<PersistValue>): acp.Permis
 }
 
 export class CodexElicitationHandler implements ElicitationHandler {
-    private readonly connection: acp.AgentSideConnection;
+    private readonly connection: AcpClientConnection;
     private readonly sessionState: SessionState;
     // In Rust, the MCP elicitation handler receives ElicitationRequestEvent directly from the MCP
     // protocol layer, where id is set to "mcp_tool_call_approval_<call_id>" — the call ID is extracted
@@ -85,7 +86,7 @@ export class CodexElicitationHandler implements ElicitationHandler {
     // (threadId, serverName).
     private readonly pendingMcpApprovals = new Map<string, string>();
 
-    constructor(connection: acp.AgentSideConnection, sessionState: SessionState) {
+    constructor(connection: AcpClientConnection, sessionState: SessionState) {
         this.connection = connection;
         this.sessionState = sessionState;
     }
@@ -111,11 +112,11 @@ export class CodexElicitationHandler implements ElicitationHandler {
     ): Promise<McpServerElicitationRequestResponse> {
         try {
             const { request, correlatedCallId } = this.buildPermissionRequest(params);
-            const response = await this.connection.requestPermission(request);
+            const response = await this.connection.request(acp.methods.client.session.requestPermission, request);
             if (correlatedCallId !== undefined && response.outcome.outcome !== "cancelled") {
                 const optionId = response.outcome.optionId;
                 if (optionId !== McpApprovalOptionId.Decline) {
-                    await this.connection.sessionUpdate({
+                    await this.connection.notify(acp.methods.client.session.update, {
                         sessionId: this.sessionState.sessionId,
                         update: { sessionUpdate: "tool_call_update", toolCallId: correlatedCallId, status: "in_progress" },
                     });

src/CodexEventHandler.ts

@@ -6,7 +6,7 @@ import type {
 import type {SessionState} from "./CodexAcpServer";
 import * as acp from "@agentclientprotocol/sdk";
 import {type PlanEntry, RequestError} from "@agentclientprotocol/sdk";
-import {ACPSessionConnection, type UpdateSessionEvent} from "./ACPSessionConnection";
+import {ACPSessionConnection, type AcpClientConnection, type UpdateSessionEvent} from "./ACPSessionConnection";
 import type {
     AccountRateLimitsUpdatedNotification,
     AgentMessageDeltaNotification,
@@ -59,7 +59,7 @@ export { stripShellPrefix };
 
 export class CodexEventHandler {
 
-    private readonly connection: acp.AgentSideConnection;
+    private readonly connection: AcpClientConnection;
     private readonly sessionState: SessionState;
     private failure: RequestError | null = null;
     private readonly activeFuzzyFileSearchSessions = new Set<string>();
@@ -70,7 +70,7 @@ export class CodexEventHandler {
     private readonly terminalCommandIds = new Set<string>();
     private readonly terminalCommandOutputIds = new Set<string>();
 
-    constructor(connection: acp.AgentSideConnection, sessionState: SessionState) {
+    constructor(connection: AcpClientConnection, sessionState: SessionState) {
         this.connection = connection;
         this.sessionState = sessionState;
     }