diff --git a/crates/rust-analyzer/src/lsp/ext.rs b/crates/rust-analyzer/src/lsp/ext.rs
index e1677cbcda..f50cbba7ac 100644
--- a/crates/rust-analyzer/src/lsp/ext.rs
+++ b/crates/rust-analyzer/src/lsp/ext.rs
@@ -1,5 +1,9 @@
 //! rust-analyzer extensions to the LSP.
 
+// Note when adding new resolve payloads, add a #[serde(default)] on boolean fields as some clients
+// might strip `false` values from the JSON payload due to their reserialization logic turning false
+// into null which will then cause them to be omitted in the resolve request. See https://github.com/rust-lang/rust-analyzer/issues/18767
+
 #![allow(clippy::disallowed_types)]
 
 use std::ops;
@@ -829,6 +833,7 @@ pub struct CompletionResolveData {
     pub version: Option<i32>,
     #[serde(skip_serializing_if = "Option::is_none", default)]
     pub trigger_character: Option<char>,
+    #[serde(default)]
     pub for_ref: bool,
     pub hash: String,
 }
diff --git a/docs/dev/lsp-extensions.md b/docs/dev/lsp-extensions.md
index 826ce11244..21ac3a5a26 100644
--- a/docs/dev/lsp-extensions.md
+++ b/docs/dev/lsp-extensions.md
@@ -1,5 +1,5 @@
 <!---
-lsp/ext.rs hash: 512c06cd8b46a21d
+lsp/ext.rs hash: 6dd762ae19630ec0
 
 If you need to change the above hash to make the test pass, please check if you
 need to adjust this doc as well and ping this issue: