pypa/pip · error · PEP723Exception

File does not contain

Error message

File does not contain {name!r} metadata: {scriptfile!r}

What it means

pip's PEP 723 support was invoked on a script file, but the file contains no '# /// script' inline metadata block at all. Without this block, pip cannot determine which dependencies to install for the script.

Solutions

1. Add a PEP 723 metadata block to the script with the required dependencies
2. Alternatively, pre-install the dependencies in your environment and run the script directly with 'python script.py' instead of pip

Example fix

# before — script.py has no metadata block
import requests
print(requests.__version__)

# after
# /// script
# dependencies = ["requests"]
# ///
import requests
print(requests.__version__)

import re

REGEX = r"(?m)^# /// (?P<type>[a-zA-Z0-9-]+)$\s(?P<content>(^#(| .*)$\s)+)^# ///$"

def has_pep723_metadata(filepath: str) -> bool:
    with open(filepath) as f:
        script = f.read()
    return any(m.group("type") == "script" for m in re.finditer(REGEX, script))

if not has_pep723_metadata("script.py"):
    print("No PEP 723 metadata block found — add one or install deps manually")

import re

def contains_pep723_block(filepath: str) -> bool:
    """Type guard: True if the script has a '# /// script' metadata block."""
    regex = r"(?m)^# /// (?P<type>[a-zA-Z0-9-]+)$\s(?P<content>(^#(| .*)$\s)+)^# ///$"
    with open(filepath) as f:
        return any(m.group("type") == "script" for m in re.finditer(regex, f.read()))

from pip._internal.req.pep723 import pep723_metadata, PEP723Exception

try:
    meta = pep723_metadata("script.py")
except PEP723Exception as e:
    if "does not contain" in e.msg:
        print("Add a '# /// script' block with dependencies")
    else:
        raise

When it happens

Trigger: Running a plain Python script through pip's inline-script execution (pip run) where the script has no '# /// script' block. The regex REGEX in pep723.py found zero matches with type 'script'.

Common situations: Forgetting to add inline metadata to a script before running it with pip. Running a script that was meant to use a virtual environment's pre-installed packages. Script that predates PEP 723 adoption.

Related errors

• Multiple blocks found in
• Failed to parse TOML in
• Invalid requirement
• Requested has inconsistent Name between its PEP 658…
• Requested has inconsistent Name: expected , but metadata has

AI-assisted analysis of pypa/pip@f399c37189 (2026-08-08). Data as JSON: /api/errors/7ce0055616222349. Report an issue: GitHub.

Appendix: source

Thrown at src/pip/_internal/req/pep723.py:37

    name = "script"
    matches = list(
        filter(lambda m: m.group("type") == name, re.finditer(REGEX, script))
    )

    if len(matches) > 1:
        raise PEP723Exception(f"Multiple {name!r} blocks found in {scriptfile!r}")
    elif len(matches) == 1:
        content = "".join(
            line[2:] if line.startswith("# ") else line[1:]
            for line in matches[0].group("content").splitlines(keepends=True)
        )
        try:
            metadata = tomllib.loads(content)
        except Exception as exc:
            raise PEP723Exception(f"Failed to parse TOML in {scriptfile!r}") from exc
    else:
        raise PEP723Exception(
            f"File does not contain {name!r} metadata: {scriptfile!r}"
        )

    return metadata

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