fix: improvements (layout element shuffling and allow more strategies) in experimental two-stages pipeline

[ElHachem02]

Checklist:

• Documentation has been updated, if necessary.
• Examples have been added, if necessary.
• Tests have been added, if necessary.

[github-actions]

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[dosubot]

Related Documentation

Checked 5 published document(s) in 1 knowledge base(s). No updates required.

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[Copilot]

Pull request overview

This PR introduces changes to the prompt building logic in the threaded layout VLM pipeline, modifying how layout information is incorporated into VLM prompts. However, the implementation appears to contain incomplete experimental code that needs refinement before merging.

Key changes:

• Adds logic to filter prompts and only augment "Convert this page to docling." base prompts
• Introduces random shuffling of layout elements and experimental table tag replacement
• Changes prompt composition to use only layout information, discarding the base instruction text

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[Copilot]

Debug print statement should be removed before merging to production. Consider using the existing _log.debug() instead if this logging is needed.

Suggested change

	print("Found a table!")
	_log.debug("Found a table!")

[Copilot]

The purpose of replacing table tags with "otsl" is unclear and lacks documentation. This appears to be experimental code that should either be explained with a comment or removed if not needed.

Suggested change

	print("Found a table!")
	print("Found a table!")
	# Experimental: Replace 'table' tag with 'otsl' for downstream processing.
	# TODO: Document the reason for this replacement or remove if not needed.

[Copilot]

Randomly shuffling layout elements will produce non-deterministic results and makes the output unreproducible. This is problematic for testing, debugging, and consistent user experience. If shuffling is intentional for training/testing purposes, it should be: (1) documented with a clear explanation, (2) controlled by a configuration parameter, and (3) use a seeded random generator for reproducibility.

[Copilot]

This change completely discards the base_prompt and replaces it with only the layout information. The original implementation would concatenate them (base_prompt + layout_injection). This is a breaking change that removes the instruction text "Convert this page to docling." from the prompt. If intentional, this should be documented and the implications explained.

Suggested change

	augmented_prompt = layout_injection
	augmented_prompt = base_prompt + "\n" + layout_injection

[Copilot]

Debug print statement should be removed before merging to production. The existing _log.debug() at line 148-150 already logs this information appropriately.

Suggested change

print(f"final prompt is {augmented_prompt}")

[Copilot]

The random module import should be placed with the other standard library imports at the top of the file (after line 12, before the third-party imports), following Python's PEP 8 style guide for import ordering.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 11 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...erimental/pipeline/threaded_layout_vlm_pipeline.py	0.00%	11 Missing ⚠️

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