GitHub Copilot Sessions

Locate past GitHub Copilot CLI sessions matching a project and/or topic, then summarize them. Session event logs reach tens of MB. Never read a full events.jsonl into the main context — rank cheaply with the bundled script, then dispatch one subagent per top candidate to grep just the relevant lines.

Storage facts

Two complementary stores live under ~/.copilot/:

1. ~/.copilot/session-store.db (SQLite WAL) — the fast BM25 path.

• search_index is an FTS5 virtual table; its built-in rank column is BM25 (lower = better).
• ~15 k indexed rows. source_type ∈ {turn, checkpoint_overview, checkpoint_history, checkpoint_work_done, checkpoint_technical_details, checkpoint_files, checkpoint_next_steps, workspace_artifact}.
• sessions(id, cwd, repository, branch, summary, created_at, updated_at, host_type).
• turns(session_id, turn_index, user_message, assistant_response, timestamp).

2. ~/.copilot/session-state/<UUID>/events.jsonl — per-session raw event log (one JSON obj/line).

• Each dir also has workspace.yaml with summary:, created_at:, cwd:, repository:.
• High-value event types: session.task_complete → data.summary (markdown recap); session.compaction_complete → data.summaryContent (~9 KB XML); user.message, assistant.message, tool.execution_complete.
• Session id = the UUID directory name.
• Used as BM25 fallback (--no-db) and for the deep-read step.