diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index b668f2f..af7a50a 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -32,6 +32,12 @@ jobs:
       - name: Run tests (skip slow integration tests)
         run: uv run pytest tests/ -v --tb=short --ignore=tests/test_integration.py
 
+      - name: Smoke-test wheel with clean dependency resolution
+        run: |
+          uv build --wheel --out-dir dist-smoke
+          WHEEL=$(find dist-smoke -name '*.whl' -print -quit)
+          timeout 30s uvx --refresh --from "$WHEEL" paper-intelligence </dev/null
+
   lint:
     name: Lint
     runs-on: ubuntu-latest
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 02d98dd..3d83a63 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+## [0.5.2] - 2026-08-28
+
+### Fixed
+- Pin the MCP Python SDK below v2 because the server uses the v1 FastMCP API; clean installs no longer resolve an incompatible SDK that crashes at startup.
+- CI now launches the CLI from a freshly built wheel without relying on the repository lockfile.
+
 ## [0.5.1] - 2026-08-28
 
 ### Fixed
diff --git a/paper_intelligence/_version.py b/paper_intelligence/_version.py
index 16ff2e8..fb0fa92 100644
--- a/paper_intelligence/_version.py
+++ b/paper_intelligence/_version.py
@@ -4,7 +4,7 @@
 
 from typing import Optional
 
-__version__ = "0.5.1"
+__version__ = "0.5.2"
 
 # Version compatibility rules:
 # - Major version change = incompatible, must re-process
diff --git a/pyproject.toml b/pyproject.toml
index b83bb67..a80d198 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,7 +23,7 @@ classifiers = [
     "Topic :: Text Processing :: Indexing",
 ]
 dependencies = [
-    "mcp[cli]>=1.0.0",
+    "mcp[cli]>=1.0.0,<2",
     "marker-pdf>=1.0.0",
     "chromadb>=0.4.0",
     "llama-index-core>=0.10.0",
diff --git a/uv.lock b/uv.lock
index dab0840..bbd27d5 100644
--- a/uv.lock
+++ b/uv.lock
@@ -2907,7 +2907,7 @@ requires-dist = [
     { name = "llama-index-embeddings-huggingface", specifier = ">=0.2.0" },
     { name = "llama-index-vector-stores-chroma", specifier = ">=0.1.0" },
     { name = "marker-pdf", specifier = ">=1.0.0" },
-    { name = "mcp", extras = ["cli"], specifier = ">=1.0.0" },
+    { name = "mcp", extras = ["cli"], specifier = ">=1.0.0,<2" },
     { name = "pydantic", specifier = ">=2.0.0" },
     { name = "pytest", marker = "extra == 'dev'", specifier = ">=7.0.0" },
     { name = "pytest-asyncio", marker = "extra == 'dev'", specifier = ">=0.21.0" },