chat: migrate supported workspace MCP servers

src/vs/sessions/AI_CUSTOMIZATIONS.md

@@ -51,7 +51,9 @@ Core workbench registrations may expose Local, Copilot CLI, and Claude harnesses
 
 ### `ICustomizationMigrationService`
 
-This shared workbench service computes customization migrations for an explicit chat session. File migrations include source URIs and migratable-configuration metadata for flows that need source type and storage; MCP migrations report known servers' binary harness compatibility together with discovery and policy-coverage state. The service also produces a localized, harness-specific hint summarizing available file migrations for UI consumers.
+This shared workbench service computes customization migrations for an explicit chat session. File migrations include source URIs and migratable-configuration metadata for flows that need source type and storage. Its MCP migration domain owns source canonicalization, destination representability, candidate planning, pre-write revalidation, guarded execution, and typed failure reasons. MCP results also retain the full compatibility inventory, discovery state, and policy coverage. The service produces a localized, harness-specific hint summarizing available migrations for UI consumers.
+
+`CustomizationMigrationModel` owns the editor's reactive migration lifecycle: active-session and MCP refresh inputs, async sequencing, loading/error state, candidates, and destination folders. The management editor owns only selection, rendering, confirmation, and user notifications.
 
 ### `IHarnessDescriptor`
 

src/vs/workbench/contrib/chat/browser/agentSessions/agentHost/agentHostCustomizationService.ts

@@ -484,14 +484,17 @@ class WorkbenchAgentHostCustomizationService extends AbstractAgentHostCustomizat
 			return undefined;
 		}
 		const sessionState = this._readSessionState(sessionResource);
+		const workingDirectories = sessionState === undefined
+			? this._provisionalSessionService.getProvisionalWorkingDirectories(sessionResource)?.map(uri => uri.toString())
+			: sessionState.workingDirectories;
 		const rootState = target.connection.rootState.value;
 		const channel = target.backendSession.toString();
 		return {
 			customizations: sessionState?.customizations ?? [],
 			resourceUris: target.connection.resourceUris,
 			folderPickerDecision: readSessionFolderPickerDecision(sessionState?._meta),
-			workingDirectory: sessionState?.workingDirectories?.[0],
-			workingDirectories: sessionState?.workingDirectories,
+			workingDirectory: workingDirectories?.[0],
+			workingDirectories,
 			rootConfig: rootState && !(rootState instanceof Error) ? rootState.config : undefined,
 			isBundledMcpServer: (pluginUri, serverName) => this._activeClientService.isBundledMcpServer(pluginUri, serverName),
 			authenticate: request => target.connection.authenticate(request),

src/vs/workbench/contrib/chat/browser/agentSessions/agentHost/agentHostMcpServerSupport.ts

@@ -620,14 +620,14 @@ function projectMcpServerConfiguration(launch: McpServerLaunch): IMcpServerConfi
 				command: launch.command,
 				args: launch.args.length > 0 ? [...launch.args] : undefined,
 				env: Object.keys(launch.env).length > 0 ? { ...launch.env } : undefined,
-				envFile: launch.envFile,
-				cwd: launch.cwd,
+				...(launch.envFile !== undefined ? { envFile: launch.envFile } : {}),
+				...(launch.cwd !== undefined ? { cwd: launch.cwd } : {}),
 			};
 		case McpServerTransportType.HTTP:
 			return {
 				type: McpServerType.REMOTE,
 				url: launch.uri.toString(),
-				headers: launch.headers.length > 0 ? Object.fromEntries(launch.headers) : undefined,
+				...(launch.headers.length > 0 ? { headers: Object.fromEntries(launch.headers) } : {}),
 			};
 	}
 }

src/vs/workbench/contrib/chat/browser/agentSessions/agentHost/agentHostUntitledProvisionalSessionService.ts

@@ -105,6 +105,9 @@ export interface IAgentHostUntitledProvisionalSessionService {
 	 */
 	get(sessionResource: URI): URI | undefined;
 
+	/** Working directories used to create the current provisional generation. */
+	getProvisionalWorkingDirectories(sessionResource: URI): readonly URI[] | undefined;
+
 	/**
 	 * Initial config the editor window applies to every new Agent Host session.
 	 * Returns `undefined` in the Agents window, where the sessions provider owns
@@ -373,6 +376,14 @@ export class AgentHostUntitledProvisionalSessionService extends Disposable imple
 		return this._generationMatchingDesiredState(entry)?.backendSession;
 	}
 
+	getProvisionalWorkingDirectories(sessionResource: URI): readonly URI[] | undefined {
+		const entry = this._entries.get(sessionResource);
+		if (!entry || entry.disposed) {
+			return undefined;
+		}
+		return this._generationMatchingDesiredState(entry)?.workingDirectories;
+	}
+
 	private _computeWorkingDirectories(primary: URI | undefined, provider: string): readonly URI[] | undefined {
 		return computeWorkingDirectories(primary, this._workspaceContextService.getWorkspace().folders.map(folder => folder.uri), this._agentHostService.rootState.value, provider);
 	}