diff --git a/codex-rs/mcp-server/src/lib.rs b/codex-rs/mcp-server/src/lib.rs
index 4a4ff054be..cb14fec3e2 100644
--- a/codex-rs/mcp-server/src/lib.rs
+++ b/codex-rs/mcp-server/src/lib.rs
@@ -1,4 +1,5 @@
 //! Prototype MCP server.
+#![recursion_limit = "256"]
 #![deny(clippy::print_stdout, clippy::print_stderr)]
 
 use std::io::ErrorKind;