A file an agent writes with the host's own edit tools into a main checkout two or more live sessions share is not refused. On 2026-10-28 the record writers (capture, intent, decide, spec close and the index generator) began refusing a shared main checkout through a per-session occupancy marker (iss-2610240859590333), but an agent's direct Write or Edit of a record file, or of any tracked file, goes through the host's file tools, which the shell guard never sees. The 2026-10-24 incident used the verbs, so the verbs were closed first; the same mistake made with the file tools lands the same way.

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mentions1

• iss-2610240859590333A session wrote records into the main checkout's working tree on main while another live session (abcd-0d) was working in the same checkout, because nothing enforces the rule that a concurrent session works in its own worktree. On 2026-10-24 this session ran capture, intent, decide --adr and go generate from the main checkout: an issue record, an intent draft, an ADR and two regenerated index regions landed in the shared tree, the regenerated indexes folding in a peer's untracked draft. Nothing refused or warned. capture, intent and decide write into whichever checkout they run in; the guard judges shell commands and questions, not where records are written; and the CONCURRENCY rules domain, which carries the rule, recalls only on prompts about worktrees, peers or sessions, so a prompt saying 'file the decision record' never injected it. The agent also skipped the required scan (session listing and abcd peers) before mutating. The rule held only as prose.