diff --git a/lib/container.sh b/lib/container.sh
index af3882c..224b1c5 100644
--- a/lib/container.sh
+++ b/lib/container.sh
@@ -17,6 +17,7 @@ generate_container_scripts() {
 # Claude Code wrapper — runs claude inside the agents container.
 # CS Core on the host calls this instead of the real claude binary.
 CONTAINER_NAME="${container_name}"
+PROJECT_DIR="${project_dir}"
 RUNTIME="\$(command -v podman || command -v docker || true)"
 
 if [[ -z "\$RUNTIME" ]]; then
@@ -30,11 +31,21 @@ if ! "\$RUNTIME" container inspect "\$CONTAINER_NAME" --format '{{.State.Running
     exit 1
 fi
 
+# Use PWD as workdir only if it is inside the mounted project tree.
+# When CS Core's server process calls claude --version its cwd is the
+# core directory (~/.context-studio/core) which is NOT mounted, causing
+# podman exec --workdir to fail. Fall back to PROJECT_DIR in that case.
+if [[ "\$PWD" == "\$PROJECT_DIR"* ]]; then
+    WORKDIR="\$PWD"
+else
+    WORKDIR="\$PROJECT_DIR"
+fi
+
 # Pass through TTY if available, relay working directory into container
 if [ -t 0 ]; then
-    exec "\$RUNTIME" exec -it --workdir "\$PWD" "\$CONTAINER_NAME" claude "\$@"
+    exec "\$RUNTIME" exec -it --workdir "\$WORKDIR" "\$CONTAINER_NAME" claude "\$@"
 else
-    exec "\$RUNTIME" exec -i  --workdir "\$PWD" "\$CONTAINER_NAME" claude "\$@"
+    exec "\$RUNTIME" exec -i  --workdir "\$WORKDIR" "\$CONTAINER_NAME" claude "\$@"
 fi
 WRAPPER
     chmod +x "$project_dir/bin/claude"