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RECAP: An End-to-End Platform for Capturing, Replaying, and Analyzing AI-Assisted Programming Interactions

AI Assisted ProgrammingCode IntelligenceDeveloper TelemetryHuman AI InteractionProgramming Education

RECAP is an open-source VS Code platform for recording, replaying, and analyzing AI-assisted programming sessions. It links GitHub Copilot chat prompts to fine-grained code edits, so researchers can inspect how developers use AI during real projects.

  • Chat logs and git histories alone cannot show which prompt led to which edit, what the developer rejected, or how the work changed over time.
  • Modern coding agents can edit multiple files across long sessions, while normal commits and short lab studies lose much of that detail.
  • This matters for educators and researchers who need evidence about AI reliance, debugging behavior, and the code effects of AI assistance.
  • A VS Code extension records Copilot chat JSON files and a shadow git history of workspace changes.
  • The shadow git store commits file saves, creates, deletes, renames, and unsaved dirty snapshots with a 5-second debounce and 30-second maximum interval.
  • The system matches Copilot text edit groups to later git diffs within a 5-minute window using fuzzy line-level comparison, then labels edits as Copilot, human, partial match, unmatched, or likely external source.
  • A web replay viewer merges chat events and code commits into one timeline with file tree, diff view, chat panel, and color-coded event markers.
  • Analysis modules classify prompts into 17 behavior codes across 6 categories, compute AI edit share by work session, and cluster prompt embeddings.
  • In a Spring 2026 university course deployment, RECAP captured 2,034 prompts from 29 students and 8,239 shadow-git commits from 41 students across 406 work sessions.
  • The assignment lasted 2 weeks and asked students to extend two LLM-based features in Zulip.
  • Prompt classification found Explain at 44%, with explain-error prompts alone at 29%; Plan and Code were each 14%, Converse was 13%, Setup was 8%, and Eval was 6%.
  • AI edit share declined over successive work sessions, with weighted linear fit r = -0.222 and p < 0.001.
  • Replay exposed concrete behavior patterns, including an 11-minute TypeError loop where prompts 17, 20, and 23 repeated the same error and Copilot produced fixes that led back to the original issue.
  • The paper presents the deployment as a platform demonstration rather than a controlled outcome study, so it does not claim improvements in developer speed, code quality, or learning outcomes.