The pyghidra-mcp wrapper bakes in GHIDRA_INSTALL_DIR via makeWrapperArgs referencing pkgs.ghidra, which makes ghidra a runtime closure dep. Adding pkgs.ghidra explicitly to home.packages caused buildEnv to merge *two* ghidra-12.0.4 store paths (one from pyghidra's propagatedBuildInputs, one from the explicit list) and fail with a path collision on GPL/DMG/LICENSE.txt. Drop the explicit add. The agent-driven workflow doesn't need the GUI; manual exploration via 'nix run nixpkgs#ghidra' is one command away if ever wanted.