Is there an extension mechanism, so that we can add our own , more specific, file formats ?

[MJonker]

In some cases the text we want to extract is in a proprietary format. Is there is an extension mechanism that we can use ?

[ltianyi992]

Yes — markitdown has a full extension mechanism via custom DocumentConverter classes.

Option 1: Register a converter directly (lightweight)

from markitdown import MarkItDown, PRIORITY_SPECIFIC_FILE_FORMAT
from markitdown._base_converter import DocumentConverter, DocumentConverterResult
from markitdown._stream_info import StreamInfo
from typing import BinaryIO, Any

class MyProprietaryConverter(DocumentConverter):
    def accepts(self, file_stream: BinaryIO, stream_info: StreamInfo, **kwargs: Any) -> bool:
        ext = (stream_info.extension or "").lower()
        return ext == ".myext"  # your format's extension

    def convert(self, file_stream: BinaryIO, stream_info: StreamInfo, **kwargs: Any) -> DocumentConverterResult:
        content = file_stream.read().decode("utf-8")  # parse your format here
        return DocumentConverterResult(markdown=f"Converted content:\n{content}")

md = MarkItDown()
md.register_converter(MyProprietaryConverter(), priority=PRIORITY_SPECIFIC_FILE_FORMAT)
result = md.convert("myfile.myext")

Option 2: Installable plugin package (shareable)

Create a Python package with a register_converters entry point:

# your_package/__init__.py
__plugin_interface_version__ = 1

def register_converters(markitdown, **kwargs):
    markitdown.register_converter(MyProprietaryConverter())

# pyproject.toml
[project.entry-points."markitdown.plugin"]
your_package = "your_package"

Then enable plugins at runtime:

md = MarkItDown(enable_plugins=True)

or via CLI:

markitdown --use-plugins myfile.myext

The accepts() method controls which files your converter handles — check stream_info.extension, stream_info.mimetype, or even peek at file_stream bytes for magic-number detection. Lower priority values take precedence over built-ins.

[everett203-beep]

That language is harder well it to me longer to learn usually u would put value to a variable and went from there