Parse tool args from CLI as JsonValue instead of just strings

cli/src/client/prompts.ts

@@ -1,6 +1,16 @@
 import { Client } from "@modelcontextprotocol/sdk/client/index.js";
 import { McpResponse } from "./types.js";
 
+// JSON value type matching the client utils
+type JsonValue =
+  | string
+  | number
+  | boolean
+  | null
+  | undefined
+  | JsonValue[]
+  | { [key: string]: JsonValue };
+
 // List available prompts
 export async function listPrompts(client: Client): Promise<McpResponse> {
   try {
@@ -17,12 +27,26 @@ export async function listPrompts(client: Client): Promise<McpResponse> {
 export async function getPrompt(
   client: Client,
   name: string,
-  args?: Record<string, string>,
+  args?: Record<string, JsonValue>,
 ): Promise<McpResponse> {
   try {
+    // Convert all arguments to strings for prompt arguments
+    const stringArgs: Record<string, string> = {};
+    if (args) {
+      for (const [key, value] of Object.entries(args)) {
+        if (typeof value === 'string') {
+          stringArgs[key] = value;
+        } else if (value === null || value === undefined) {
+          stringArgs[key] = String(value);
+        } else {
+          stringArgs[key] = JSON.stringify(value);
+        }
+      }
+    }
+
     const response = await client.getPrompt({
       name,
-      arguments: args || {},
+      arguments: stringArgs,
     });
 
     return response;