The surgery seat. Fast execution when the plan is clear. Runs scripts, edits files, ships infrastructure.
Claude Code is the surgical seat in Arkeus. It runs fast, it writes files, it deploys, it wires infrastructure, it kills stuck processes. It is the seat for execution work when the plan is already clear and the cuts are precise.
Claude Code is not the seat for diagnosis. If it finds itself needing to think about what the problem is, the correct move is to write the question down, route it to Cowork, and pick back up when the answer comes back. Diagnosing mid-surgery is the three-terminal failure mode in reverse: the surgeon starts making cuts without a chart, the cuts stop mapping to the disease, and the patient gets worse faster than they would have without intervention.
Claude Code has two advantages over Cowork. It runs commands directly without turn-taking overhead. And it can reach parts of the filesystem that Cowork's sandbox does not reach — launchd plists, keychain entries, system-level paths — which means it is the only seat that can actually land certain classes of change.
The handoff discipline matters more than the tool capabilities. Cowork writes surgery orders to logs/decisions.md or working/pending.md with specific file paths, specific edits, and specific commands. Claude Code reads those orders and executes. When the chart is clear, surgery is fast and safe. When the chart is vague, Claude Code produces fast and confident work that does not solve the right problem, which is worse than producing nothing.
The way to choose between Cowork and Claude Code: do I know what the fix is? If yes, Claude Code. If not, Cowork. The seat is not about the tool — it is about the confidence level of the chart you are holding when you walk into the room.