What are the best ways to document code while pair programming?

I have tried many methods, including using AI tools and vector databases, but the easiest and most straightforward way is to write the relevant notes directly in the notes at the beginning of the code, and reduce the intermediate steps to save time.

The best way in my opinion, is to establish a 'Comment-as-You-Code' rule, ensuring each coder articulates their logic in real-time. This way, documentation evolves naturally alongside code development, fostering clarity and mutual understanding.

While pair programming, adopting the driver-navigator model can be effective. One developer writes code while the other reviews and documents in real-time. Frequent role switches ensure continuous engagement. This approach enhances code quality, error detection, and provides clear documentation reflecting current logic and decisions. It's a proactive strategy to capture insights while they're fresh, fostering collaboration and facilitating future comprehension of the codebase.

Both should have the same thought process ,otherwise it will be a total mess ,what you intend to do from a particular code is not necessary that he can interpret it ...

I'd say adopt a live documentation approach: as one pair programs, the other annotates. This dynamic, with frequent role swaps, ensures immediate documentation of logic and decisions, enhancing clarity and future code readability.

Pair programming documentation relies on clear variable/function names, minimizing explicit comments, and using them for complexity explanations. Include major design decisions, maintain a detailed README for project context, and write meaningful commits with unit tests as executable documentation for expected behavior.

Again, the process of documentation cannot be done in a separate phase, after coding, those two processes must go in tandem to assure great code and great documentation. And so as you pair program, ensure comments capture the rationale behind decisions, not just the actions. This 'why over what' approach preserves context, aiding future understanding and maintenance.

Always keep the bigger picture in mind when documenting by embracing holistic documentation, how? While pair programming, regularly update high-level overviews like READMEs and diagrams to reflect the project's evolving purpose, structure, and dependencies, ensuring alignment and clear communication.

I would very much recommend incorporating documentation review as a regular part of the code review, and pair programming processes. Update it with every significant change to ensure it remains an accurate, up-to-date guide reflecting your project's current status.