diff --git a/Cargo.lock b/Cargo.lock
index 1b95610d5d..5ffe87651a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -684,7 +684,6 @@ dependencies = [
  "language_models",
  "log",
  "markdown",
- "once_cell",
  "open",
  "paths",
  "portable-pty",
diff --git a/crates/assistant_tools/Cargo.toml b/crates/assistant_tools/Cargo.toml
index 9ee664afd8..6d6baf2d54 100644
--- a/crates/assistant_tools/Cargo.toml
+++ b/crates/assistant_tools/Cargo.toml
@@ -62,7 +62,6 @@ which.workspace = true
 workspace-hack.workspace = true
 workspace.workspace = true
 zed_llm_client.workspace = true
-once_cell = "1.21.3"
 
 [dev-dependencies]
 client = { workspace = true, features = ["test-support"] }
diff --git a/crates/assistant_tools/src/edit_agent/create_file_parser.rs b/crates/assistant_tools/src/edit_agent/create_file_parser.rs
index 911746e922..4f416a1fc6 100644
--- a/crates/assistant_tools/src/edit_agent/create_file_parser.rs
+++ b/crates/assistant_tools/src/edit_agent/create_file_parser.rs
@@ -1,10 +1,10 @@
-use once_cell::sync::Lazy;
 use regex::Regex;
 use smallvec::SmallVec;
+use std::cell::LazyCell;
 use util::debug_panic;
 
-const START_MARKER: Lazy<Regex> = Lazy::new(|| Regex::new(r"\n?```\S*\n").unwrap());
-const END_MARKER: Lazy<Regex> = Lazy::new(|| Regex::new(r"\n```\s*$").unwrap());
+const START_MARKER: LazyCell<Regex> = LazyCell::new(|| Regex::new(r"\n?```\S*\n").unwrap());
+const END_MARKER: LazyCell<Regex> = LazyCell::new(|| Regex::new(r"\n```\s*$").unwrap());
 
 #[derive(Debug)]
 pub enum CreateFileParserEvent {