Reorder execute params: (toolCallId, params, onUpdate, ctx, signal?)

Optional signal now at the end for cleaner API

packages/coding-agent/examples/custom-tools/hello/index.ts

@@ -9,7 +9,7 @@ const factory: CustomToolFactory = (_pi) => ({
 		name: Type.String({ description: "Name to greet" }),
 	}),
 
-	async execute(_toolCallId, params) {
+	async execute(_toolCallId, params, _onUpdate, _ctx, _signal) {
 		const { name } = params as { name: string };
 		return {
 			content: [{ type: "text", text: `Hello, ${name}!` }],

packages/coding-agent/examples/custom-tools/question/index.ts

@@ -24,7 +24,7 @@ const factory: CustomToolFactory = (pi) => {
 		description: "Ask the user a question and let them pick from options. Use when you need user input to proceed.",
 		parameters: QuestionParams,
 
-		async execute(_toolCallId, params) {
+		async execute(_toolCallId, params, _onUpdate, _ctx, _signal) {
 			if (!pi.hasUI) {
 				return {
 					content: [{ type: "text", text: "Error: UI not available (running in non-interactive mode)" }],

packages/coding-agent/examples/custom-tools/subagent/index.ts

@@ -433,7 +433,7 @@ const factory: CustomToolFactory = (pi) => {
 		},
 		parameters: SubagentParams,
 
-		async execute(_toolCallId, params, signal, onUpdate, _ctx) {
+		async execute(_toolCallId, params, onUpdate, _ctx, signal) {
 			const agentScope: AgentScope = params.agentScope ?? "user";
 			const discovery = discoverAgents(pi.cwd, agentScope);
 			const agents = discovery.agents;

packages/coding-agent/examples/custom-tools/todo/index.ts

@@ -78,7 +78,7 @@ const factory: CustomToolFactory = (_pi) => {
 		// Called on session start/switch/branch/clear
 		onSession: reconstructState,
 
-		async execute(_toolCallId, params) {
+		async execute(_toolCallId, params, _onUpdate, _ctx, _signal) {
 			switch (params.action) {
 				case "list":
 					return {