diff --git a/CHANGELOG.md b/CHANGELOG.md
index fc9f155..5de879e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,32 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.3.0] - 2025-09-14
+
+### Added
+
+- Tool output schema support with comprehensive validation (#122)
+- HTTP client transport layer for MCP clients (#28)
+- Tool annotations validation for protocol compatibility (#122)
+- Server instructions support (#87)
+- Title support in server info (#119)
+- Default values for tool annotation hints (#118)
+- Notifications/initialized method implementation (#84)
+
+### Changed
+
+- Make default protocol version the latest specification version (#83)
+- Protocol version validation to ensure valid values (#80)
+- Improved tool handling for tools with no arguments (#85, #86)
+- Better error handling and response API (#109)
+
+### Fixed
+
+- JSON-RPC notification format in Streamable HTTP transport (#91)
+- Errors when title is not specified (#126)
+- Tools with missing arguments handling (#86)
+- Namespacing issues in README examples (#89)
+
 ## [0.2.0] - 2025-07-15
 
 ### Added
diff --git a/lib/mcp/version.rb b/lib/mcp/version.rb
index 55c1844..475d817 100644
--- a/lib/mcp/version.rb
+++ b/lib/mcp/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module MCP
-  VERSION = "0.2.0"
+  VERSION = "0.3.0"
 end