Various fixes for tool calling

server/src/llm/message-content.ts

@@ -146,8 +146,13 @@ export function buildOpenAIConversationMessage(message: ChatMessage) {
   return out;
 }
 
+const ANTHROPIC_NO_SERVER_TOOLS_PROMPT =
+  "This Anthropic backend path does not have server-managed tool calls. Do not claim to run shell commands, Codex tasks, web searches, or fetch URLs. If the user asks for tool execution, explain that they should switch to OpenAI or xAI in this app for tool-enabled chat.";
+
 export function getAnthropicSystemPrompt(messages: ChatMessage[]) {
-  return messages.find((message) => message.role === "system")?.content;
+  return [ANTHROPIC_NO_SERVER_TOOLS_PROMPT, messages.find((message) => message.role === "system")?.content]
+    .filter(Boolean)
+    .join("\n\n");
 }
 
 export function buildAnthropicConversationMessage(message: ChatMessage) {