diff --git a/CHANGELOG.md b/CHANGELOG.md
index c94b2de5..3620a3f0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.9.1] - 2026-03-23
+
+### Added
+
+- Allow `Client#call_tool` to accept a tool name (#266)
+
+### Fixed
+
+- Return 404 for invalid session ID in `handle_delete` (#261)
+
 ## [0.9.0] - 2026-03-20
 
 ### Added
diff --git a/lib/mcp/version.rb b/lib/mcp/version.rb
index 19b9d113..da708db5 100644
--- a/lib/mcp/version.rb
+++ b/lib/mcp/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module MCP
-  VERSION = "0.9.0"
+  VERSION = "0.9.1"
 end