Initial commit

src/app/api/v1/messages/count_tokens/route.js

@@ -0,0 +1,52 @@
+const CORS_HEADERS = {
+  "Access-Control-Allow-Origin": "*",
+  "Access-Control-Allow-Methods": "POST, OPTIONS",
+  "Access-Control-Allow-Headers": "*"
+};
+
+/**
+ * Handle CORS preflight
+ */
+export async function OPTIONS() {
+  return new Response(null, { headers: CORS_HEADERS });
+}
+
+/**
+ * POST /v1/messages/count_tokens - Mock token count response
+ */
+export async function POST(request) {
+  let body;
+  try {
+    body = await request.json();
+  } catch {
+    return new Response(JSON.stringify({ error: "Invalid JSON body" }), {
+      status: 400,
+      headers: { "Content-Type": "application/json", ...CORS_HEADERS }
+    });
+  }
+
+  // Estimate token count based on content length
+  const messages = body.messages || [];
+  let totalChars = 0;
+  for (const msg of messages) {
+    if (typeof msg.content === "string") {
+      totalChars += msg.content.length;
+    } else if (Array.isArray(msg.content)) {
+      for (const part of msg.content) {
+        if (part.type === "text" && part.text) {
+          totalChars += part.text.length;
+        }
+      }
+    }
+  }
+
+  // Rough estimate: ~4 chars per token
+  const inputTokens = Math.ceil(totalChars / 4);
+
+  return new Response(JSON.stringify({
+    input_tokens: inputTokens
+  }), {
+    headers: { "Content-Type": "application/json", ...CORS_HEADERS }
+  });
+}
+