langchain-ai/langgraph · error · ValueError

Invalid build tool: ; must be one of

Error message

Invalid build tool: {pack}; must be one of {', '.join(_BUILD_TOOLS)}

What it means

Validation in the CLI's Dockerfile generator (via _get_pip_cleanup_lines / keep_pkg_tools handling): a value in the keep_pkg_tools list is not one of the recognized build tools 'pip', 'setuptools', 'wheel' (_BUILD_TOOLS). The offending tool name and the allowed set are printed; unknown values would leave broken cleanup RUN lines in the generated image.

Solutions

1. Set keep_pkg_tools to a subset of ['pip','setuptools','wheel'], e.g. keep_pkg_tools: ['pip','setuptools']
2. Use a boolean (true) to keep all three tools if you need any of them at runtime
3. Remove misspelled entries from the keep_pkg_tools array in langgraph.json

When it happens

Trigger: Thrown at libs/cli/langgraph_cli/config.py:106 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of langchain-ai/langgraph@38031739e5 (2026-08-26). Data as JSON: /api/errors/44c2891cf19fc5b6. Report an issue: GitHub.

Appendix: source

Thrown at libs/cli/langgraph_cli/config.py:106

def _get_pip_cleanup_lines(
    install_cmd: str,
    to_uninstall: tuple[str] | None,
    pip_installer: Literal["uv", "pip"],
) -> str:
    commands = [
        f"""# -- Ensure user deps didn't inadvertently overwrite langgraph-api
RUN mkdir -p /api/langgraph_api /api/langgraph_runtime /api/langgraph_license && \
touch /api/langgraph_api/__init__.py /api/langgraph_runtime/__init__.py /api/langgraph_license/__init__.py
RUN PYTHONDONTWRITEBYTECODE=1 {install_cmd} --no-cache-dir --no-deps -e /api
# -- End of ensuring user deps didn't inadvertently overwrite langgraph-api --
# -- Removing build deps from the final image ~<:===~~~ --"""
    ]
    if to_uninstall:
        for pack in to_uninstall:
            if pack not in _BUILD_TOOLS:
                raise ValueError(
                    f"Invalid build tool: {pack}; must be one of {', '.join(_BUILD_TOOLS)}"
                )
        packs_str = " ".join(sorted(to_uninstall))
        commands.append(f"RUN pip uninstall -y {packs_str}")
        # Ensure the directories are removed entirely
        packages_rm = " ".join(
            f"/usr/local/lib/python*/site-packages/{pack}*" for pack in to_uninstall
        )
        if "pip" in to_uninstall:
            packages_rm += ' && find /usr/local/bin -name "pip*" -delete || true'
        commands.append(f"RUN rm -rf {packages_rm}")
        wolfi_packages_rm = " ".join(
            f"/usr/lib/python*/site-packages/{pack}*" for pack in to_uninstall
        )
        if "pip" in to_uninstall:
            wolfi_packages_rm += ' && find /usr/bin -name "pip*" -delete || true'
        commands.append(f"RUN rm -rf {wolfi_packages_rm}")
        if pip_installer == "uv":

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