diff --git a/crates/tinymist-query/src/analysis/ty/post_check.rs b/crates/tinymist-query/src/analysis/ty/post_check.rs
index 5343d589..a25b3cd5 100644
--- a/crates/tinymist-query/src/analysis/ty/post_check.rs
+++ b/crates/tinymist-query/src/analysis/ty/post_check.rs
@@ -197,6 +197,8 @@ impl<'a, 'w> PostTypeCheckWorker<'a, 'w> {
                 log::debug!("post check paren target: {container_ty:?}::{is_before:?}");
 
                 let mut resp = SignatureReceiver::default();
+                // todo: this is legal, but it makes it sometimes complete itself.
+                // e.g. completing `""` on `let x = ("|")`
                 resp.bounds.lbs.push(container_ty.clone());
 
                 let target = ParamTarget::positional_from_before(true);
diff --git a/crates/tinymist-query/src/completion.rs b/crates/tinymist-query/src/completion.rs
index 4f85ffdb..c7fda9e4 100644
--- a/crates/tinymist-query/src/completion.rs
+++ b/crates/tinymist-query/src/completion.rs
@@ -6,7 +6,7 @@ use once_cell::sync::Lazy;
 use regex::{Captures, Regex};
 
 use crate::{
-    analysis::{BuiltinTy, Ty},
+    analysis::{BuiltinTy, InsTy, Ty},
     prelude::*,
     syntax::DerefTarget,
     upstream::{autocomplete, complete_path, CompletionContext},
@@ -132,7 +132,19 @@ impl StatefulRequest for CompletionRequest {
         let is_incomplete = false;
 
         let mut items = completion_result.or_else(|| {
-            let cc_ctx = CompletionContext::new(ctx, doc, &source, cursor, explicit)?;
+            let mut cc_ctx = CompletionContext::new(ctx, doc, &source, cursor, explicit)?;
+
+            // Exclude it self from auto completion
+            // e.g. `#let x = (1.);`
+            let self_ty = cc_ctx.leaf.cast::<ast::Expr>().and_then(|exp| {
+                let v = cc_ctx.ctx.mini_eval(exp)?;
+                Some(Ty::Value(InsTy::new(v)))
+            });
+
+            if let Some(self_ty) = self_ty {
+                cc_ctx.seen_types.insert(self_ty);
+            };
+
             let (offset, ic, mut completions, completions_items2) = autocomplete(cc_ctx)?;
             if !completions_items2.is_empty() {
                 completion_items_rest = Some(completions_items2);
diff --git a/crates/tinymist-query/src/fixtures/completion/paren_string.typ b/crates/tinymist-query/src/fixtures/completion/paren_string.typ
new file mode 100644
index 00000000..b994c9ee
--- /dev/null
+++ b/crates/tinymist-query/src/fixtures/completion/paren_string.typ
@@ -0,0 +1,2 @@
+
+#let font-any = /* range after 3..4 */ ("");
diff --git a/crates/tinymist-query/src/fixtures/completion/snaps/test@paren_string.typ.snap b/crates/tinymist-query/src/fixtures/completion/snaps/test@paren_string.typ.snap
new file mode 100644
index 00000000..dd178e57
--- /dev/null
+++ b/crates/tinymist-query/src/fixtures/completion/snaps/test@paren_string.typ.snap
@@ -0,0 +1,12 @@
+---
+source: crates/tinymist-query/src/completion.rs
+description: "Completion on \" (41..42)"
+expression: "JsonRepr::new_pure(results)"
+input_file: crates/tinymist-query/src/fixtures/completion/paren_string.typ
+---
+[
+ {
+  "isIncomplete": false,
+  "items": []
+ }
+]
diff --git a/crates/tinymist-query/src/upstream/complete.rs b/crates/tinymist-query/src/upstream/complete.rs
index 6af2ed5f..8278d279 100644
--- a/crates/tinymist-query/src/upstream/complete.rs
+++ b/crates/tinymist-query/src/upstream/complete.rs
@@ -18,7 +18,7 @@ use unscanny::Scanner;
 
 use super::{plain_docs_sentence, summarize_font_family};
 use crate::adt::interner::Interned;
-use crate::analysis::{analyze_expr, analyze_import, analyze_labels, DynLabel};
+use crate::analysis::{analyze_expr, analyze_import, analyze_labels, DynLabel, Ty};
 use crate::AnalysisContext;
 
 mod ext;
@@ -964,6 +964,7 @@ pub struct CompletionContext<'a, 'w> {
     pub completions2: Vec<lsp_types::CompletionItem>,
     pub incomplete: bool,
     pub seen_casts: HashSet<u128>,
+    pub seen_types: HashSet<Ty>,
     pub seen_fields: HashSet<Interned<str>>,
 }
 
@@ -994,6 +995,7 @@ impl<'a, 'w> CompletionContext<'a, 'w> {
             completions: vec![],
             completions2: vec![],
             seen_casts: HashSet::new(),
+            seen_types: HashSet::new(),
             seen_fields: HashSet::new(),
         })
     }
diff --git a/crates/tinymist-query/src/upstream/complete/ext.rs b/crates/tinymist-query/src/upstream/complete/ext.rs
index 78ca1a8f..aa338b86 100644
--- a/crates/tinymist-query/src/upstream/complete/ext.rs
+++ b/crates/tinymist-query/src/upstream/complete/ext.rs
@@ -692,8 +692,10 @@ fn type_completion(
     docs: Option<&str>,
 ) -> Option<()> {
     // Prevent duplicate completions from appearing.
-    if !ctx.seen_casts.insert(typst::util::hash128(&infer_type)) {
-        return Some(());
+    if let Some(infer_type) = infer_type {
+        if !ctx.seen_types.insert(infer_type.clone()) {
+            return Some(());
+        }
     }
 
     log::info!("type_completion: {:?}", infer_type);