diff --git a/src/channels/mod.rs b/src/channels/mod.rs
index 6ef69c6..f0399da 100644
--- a/src/channels/mod.rs
+++ b/src/channels/mod.rs
@@ -333,8 +333,8 @@ pub fn build_system_prompt(
             let _ = writeln!(prompt, "- **{name}**: {desc}");
         }
         prompt.push_str("\n## Tool Use Protocol\n\n");
-        prompt.push_str("To use a tool, wrap a JSON object in <invoke> tags:\n\n");
-        prompt.push_str("```\n<invoke>\n{\"name\": \"tool_name\", \"arguments\": {\"param\": \"value\"}}\n</invoke>\n```\n\n");
+        prompt.push_str("To use a tool, wrap a JSON object in <tool_call></tool_call> tags:\n\n");
+        prompt.push_str("```\n<tool_call>\n{\"name\": \"tool_name\", \"arguments\": {\"param\": \"value\"}}\n</tool_call>\n```\n\n");
         prompt.push_str("You may use multiple tool calls in a single response. ");
         prompt.push_str("After tool execution, results appear in <tool_result> tags. ");
         prompt