diff --git a/Cargo.lock b/Cargo.lock
index 964f5f764c48aaf535f5e2d9368b0816abf837d5..30cca7cafd7d62623b2c52c6e013616a6db1b90c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -35,7 +35,6 @@ dependencies = [
  "settings",
  "smol",
  "streaming_diff",
- "sum_tree",
  "task",
  "telemetry",
  "terminal",
diff --git a/crates/acp_thread/Cargo.toml b/crates/acp_thread/Cargo.toml
index 1c87abbfa21e3dc4b868203a09040b4356c0d1f9..5bda91742606c31f705998dbd47343873d6b4215 100644
--- a/crates/acp_thread/Cargo.toml
+++ b/crates/acp_thread/Cargo.toml
@@ -41,7 +41,6 @@ serde.workspace = true
 serde_json.workspace = true
 settings.workspace = true
 smol.workspace = true
-sum_tree.workspace = true
 streaming_diff.workspace = true
 task.workspace = true
 telemetry.workspace = true