fix(ai): Sanitize tool call IDs for Anthropic API compatibility

- Anthropic API requires tool call IDs to match pattern ^[a-zA-Z0-9_-]+$
- OpenAI Responses API generates IDs with pipe character (|) which breaks Anthropic
- Added sanitizeToolCallId() to replace invalid characters with underscores
- Fixes cross-provider handoffs from OpenAI Responses to Anthropic
- Added test to verify the fix works

packages/ai/test/cross-provider-toolcall.test.ts

@@ -0,0 +1,113 @@
+import { type Context, complete, getModel } from "../src/index.js";
+
+async function testCrossProviderToolCall() {
+	console.log("Testing cross-provider tool call handoff...\n");
+
+	// Define a simple tool
+	const tools = [
+		{
+			name: "get_weather",
+			description: "Get current weather for a location",
+			parameters: {
+				type: "object",
+				properties: {
+					location: { type: "string", description: "City name" },
+				},
+				required: ["location"],
+			},
+		},
+	];
+
+	// Create context with tools
+	const context: Context = {
+		systemPrompt: "You are a helpful assistant. Use the get_weather tool when asked about weather.",
+		messages: [{ role: "user", content: "What is the weather in Paris?" }],
+		tools,
+	};
+
+	try {
+		// Step 1: Get tool call from GPT-5
+		console.log("Step 1: Getting tool call from GPT-5...");
+		const gpt5 = getModel("openai", "gpt-5-mini");
+		const gpt5Response = await complete(gpt5, context);
+		context.messages.push(gpt5Response);
+
+		// Check for tool calls
+		const toolCalls = gpt5Response.content.filter((b) => b.type === "toolCall");
+		console.log(`GPT-5 made ${toolCalls.length} tool call(s)`);
+
+		if (toolCalls.length > 0) {
+			const toolCall = toolCalls[0];
+			console.log(`Tool call ID: ${toolCall.id}`);
+			console.log(`Tool call contains pipe: ${toolCall.id.includes("|")}`);
+			console.log(`Tool: ${toolCall.name}(${JSON.stringify(toolCall.arguments)})\n`);
+
+			// Add tool result
+			context.messages.push({
+				role: "toolResult",
+				toolCallId: toolCall.id,
+				toolName: toolCall.name,
+				content: JSON.stringify({
+					location: "Paris",
+					temperature: "22°C",
+					conditions: "Partly cloudy",
+				}),
+				isError: false,
+			});
+
+			// Step 2: Send to Claude Haiku for follow-up
+			console.log("Step 2: Sending to Claude Haiku for follow-up...");
+			const haiku = getModel("anthropic", "claude-3-5-haiku-20241022");
+
+			try {
+				const haikuResponse = await complete(haiku, context);
+				console.log("✅ Claude Haiku successfully processed the conversation!");
+				console.log("Response content types:", haikuResponse.content.map((b) => b.type).join(", "));
+				console.log("Number of content blocks:", haikuResponse.content.length);
+				console.log("Stop reason:", haikuResponse.stopReason);
+				if (haikuResponse.error) {
+					console.log("Error message:", haikuResponse.error);
+				}
+
+				// Print all response content
+				for (const block of haikuResponse.content) {
+					if (block.type === "text") {
+						console.log("\nClaude text response:", block.text);
+					} else if (block.type === "thinking") {
+						console.log("\nClaude thinking:", block.thinking);
+					} else if (block.type === "toolCall") {
+						console.log("\nClaude tool call:", block.name, block.arguments);
+					}
+				}
+
+				if (haikuResponse.content.length === 0) {
+					console.log("⚠️  Claude returned an empty response!");
+				}
+			} catch (error) {
+				console.error("❌ Claude Haiku failed to process the conversation:");
+				console.error("Error:", error);
+
+				// Check if it's related to the tool call ID
+				if (error instanceof Error && error.message.includes("tool")) {
+					console.error("\n⚠️  This appears to be a tool call ID issue!");
+					console.error("The pipe character (|) in OpenAI Response API tool IDs might be causing problems.");
+				}
+			}
+		} else {
+			console.log("No tool calls were made by GPT-5");
+		}
+	} catch (error) {
+		console.error("Test failed:", error);
+	}
+}
+
+// Set API keys from environment or pass them explicitly
+const openaiKey = process.env.OPENAI_API_KEY;
+const anthropicKey = process.env.ANTHROPIC_API_KEY;
+
+if (!openaiKey || !anthropicKey) {
+	console.error("Please set OPENAI_API_KEY and ANTHROPIC_API_KEY environment variables");
+	process.exit(1);
+}
+
+testCrossProviderToolCall().catch(console.error);