diff --git a/crates/tabby/src/serve.rs b/crates/tabby/src/serve.rs
index 2471041cbcb8..c208a5ce4946 100644
--- a/crates/tabby/src/serve.rs
+++ b/crates/tabby/src/serve.rs
@@ -55,6 +55,7 @@ Install following IDE / Editor extensions to get started with [Tabby](https://gi
         completion::CompletionRequest,
         completion::CompletionResponse,
         completion::Segments,
+        completion::Declaration,
         completion::Choice,
         completion::Snippet,
         completion::DebugOptions,
diff --git a/crates/tabby/src/services/completion.rs b/crates/tabby/src/services/completion.rs
index d0f9b7398a13..1ff3b4c2e424 100644
--- a/crates/tabby/src/services/completion.rs
+++ b/crates/tabby/src/services/completion.rs
@@ -109,8 +109,8 @@ pub struct Segments {
     suffix: Option<String>,
 
     /// The relative path of the file that is being edited.
-    /// When git_url is set, this is the path of the file in the git repository.
-    /// When git_url is empty, this is the path of the file in the workspace.
+    /// - When `git_url` is set, this is the path of the file in the git repository.
+    /// - When `git_url` is empty, this is the path of the file in the workspace.
     filepath: Option<String>,
 
     /// The remote URL of the current git repository.
@@ -118,10 +118,28 @@ pub struct Segments {
     /// or the git repository does not have a remote URL.
     git_url: Option<String>,
 
+    /// The relevant declaration code snippets provided by editor.
+    /// It'll contains declarations extracted from `prefix` segments using LSP.
+    declarations: Option<Vec<Declaration>>,
+
     /// Clipboard content when requesting code completion.
     clipboard: Option<String>,
 }
 
+/// A snippet of declaration code that is relevant to the current completion request.
+#[derive(Serialize, Deserialize, ToSchema, Clone, Debug)]
+pub struct Declaration {
+    /// Filepath of the file where the snippet is from.
+    /// - When the file belongs to the same workspace as the current file,
+    ///   this is a relative filepath, that has the same root as the current file.
+    /// - When the file located outside the workspace, such as in a dependency package,
+    ///   this is a file URI with an absolute filepath.
+    filepath: String,
+
+    /// Body of the snippet.
+    body: String,
+}
+
 impl From<Segments> for api::event::Segments {
     fn from(val: Segments) -> Self {
         Self {
diff --git a/crates/tabby/src/services/completion/completion_prompt.rs b/crates/tabby/src/services/completion/completion_prompt.rs
index d76f1d3229d4..8c77ff378e43 100644
--- a/crates/tabby/src/services/completion/completion_prompt.rs
+++ b/crates/tabby/src/services/completion/completion_prompt.rs
@@ -195,6 +195,7 @@ mod tests {
             suffix,
             filepath: None,
             git_url: None,
+            declarations: None,
             clipboard: None,
         }
     }