Use when the user asks "which cairn am I using?", "what server is this?", "am I on local or remote?", "how do I switch cairns?", or similar questions about the current cairn MCP connection. Calls `whoami` to read transport, endpoint, and the list of registered cairns; explains how to switch.
Use when the user wants to seed a fresh cairn from an existing code repository's accumulated history — README, docs, git log, PR descriptions, CHANGELOG. Walks the repo, drafts a single batched proposal of inferred collaborators / decisions / findings / open questions / actions, gets one consent round, then writes each item to the cairn with correctly backdated dates and structured PR / commit provenance.
Use when the user assigns pending work to someone (themselves or another collaborator) — "I'll handle X", "can you take care of Y by Friday?", "P will do Z". Records the action item via the `add_action` MCP tool (or `cairn action add` CLI). Distinct from a *decision* (commitment with rationale), *finding* (observed fact), and *open question* (uncertainty awaiting resolution).
Use when the user expresses a commitment with rationale that the team is making — "we'll go with…", "let's use X", "we decided to…", "I'm going to switch to…". Records the decision via the `add_decision` MCP tool (or `cairn decision add` CLI), attributed to the appropriate collaborator. Distinct from a *finding* (an observed fact), an *open question* (uncertainty awaiting resolution), and an *action item* (assigned pending work).
Use when the user says they have finished a task that corresponds to an action item ("I'm done with the outline", "that's shipped", "rerun is complete"). Updates `state/action_items.yaml` so status becomes `complete`, with completion timestamp and completer recorded. Keeps history — the entry is never deleted.
Use when the user expresses something they want recorded as a finding ("we just learned that…", "remember this finding…", "log that…", "we discovered…"). Writes a new markdown file under knowledge/findings/ with proper YAML frontmatter (date, author, related references). The author is the human, not you. If the user is on an exploration (a non-main git branch in the cairn), the finding records that exploration's name.
Use when starting a session inside this cairn (or when the user asks "what's going on with this project?") to load enough context to be useful, without dumping the entire knowledge base into the prompt. Loads PROJECT.md, the collaborator list, and a project-status summary, then identifies the current user.
Use when the user wraps up a cairn exploration — either because the work has been merged into main, or because they're abandoning the direction. Records the closure in the exploration's manifest and moves its row from the "Active explorations" table to a "Closed explorations" section in explorations/README.md. Pairs with the start-exploration skill.