Context

Synthesize a prose context primer from past sessions on this repo.

Steps

1. Fetch the primer. Call the get_context_primer MCP tool (pass cwd if a path was given).
2. Synthesize, don't dump. From the JSON, write: prior decisions, what was tried/abandoned, and the current open thread.
3. Anchor the open thread on the most-recent session's closing — closing.user is the last thing you actually typed and closing.assistant is the assistant's last substantive reply (outcomes like "PR is up: …" survive); branch is the branch you left off on.
4. Drill into a session worth expanding. If one primer session needs more than its opening/closing (an ambiguous open thread, a decision you need the details of), get its full arc from get_session_digest: resolve the session's filePath via search_sessions (a distinctive phrase from its intent plus the repo as project), then digest that path. Expand a specific exchange with get_session_messages(offset: exchanges[].index) — don't page from 0.
5. Keep it tight — a short brief the user can act on, not a transcript.

Guidelines

• Prefer the most recent + most-edited files as the likely active surface.
• If the primer is empty, say so plainly; don't invent history.