diff --git a/CHANGELOG.md b/CHANGELOG.md
index c85fb7a..02d98dd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+## [0.5.1] - 2026-08-28
+
+### Fixed
+- Runtime `paper_intelligence.__version__` now matches the released package version, with Hatch configured to use it as the single version source.
+
 ## [0.5.0] - 2026-08-28
 
 ### Changed
diff --git a/paper_intelligence/_version.py b/paper_intelligence/_version.py
index 2f2854b..16ff2e8 100644
--- a/paper_intelligence/_version.py
+++ b/paper_intelligence/_version.py
@@ -4,7 +4,7 @@
 
 from typing import Optional
 
-__version__ = "0.2.0"
+__version__ = "0.5.1"
 
 # Version compatibility rules:
 # - Major version change = incompatible, must re-process
diff --git a/pyproject.toml b/pyproject.toml
index e115432..b83bb67 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "paper-intelligence"
-version = "0.5.0"
+dynamic = ["version"]
 description = "MCP server enabling AI agents to efficiently search and understand PDF documents"
 readme = "README.md"
 requires-python = ">=3.10"
@@ -56,6 +56,9 @@ paper-intelligence = "paper_intelligence.server:main"
 requires = ["hatchling"]
 build-backend = "hatchling.build"
 
+[tool.hatch.version]
+path = "paper_intelligence/_version.py"
+
 [tool.hatch.build.targets.wheel]
 packages = ["paper_intelligence"]
 
diff --git a/uv.lock b/uv.lock
index e7a4be3..dab0840 100644
--- a/uv.lock
+++ b/uv.lock
@@ -2875,7 +2875,6 @@ wheels = [
 
 [[package]]
 name = "paper-intelligence"
-version = "0.5.0"
 source = { editable = "." }
 dependencies = [
     { name = "chromadb" },