spawner-pointer

A child session is told where its spawner works — one line naming that session's worktree and branch — because the child's own worktree is branched off the base, so the spawner's in-flight work is absent from it and invisible to the spec pointer.

raw source

A session launched from inside another session gets a worktree branched off the base branch, never off its spawner. So everything that session has in flight — a spec node it just created, an edit it has not landed — is absent from the child's tree. It is also invisible to spec-pointer, which resolves the prompt's **id** against the spec index of the backend's own checkout: a node living only on the spawner's branch simply is not there, and spec-pointer's fail-quiet rule means nothing says so. The child is then blind to the very context it was created to continue, and blind silently.

The fix is not to teach the fork or the landing about nesting. Both would have to learn a second base — what this branch forked from, distinct from what it merges into — which splits every base question in the system (the overlay's own-work diff, the ahead gate, session-eval's fork point, the review diff, the merge target) into two, and the landing would still carry the spawner's unreviewed commits into whatever the child merges into, because git merge carries ancestry. Tell the child where its spawner works instead, and let it decide whether to look. Provenance the agent can act on, not only a dashboard fold.

expanded spec

When newSession has a parent (session-nesting), it appends one line to the launch prompt: the spawner's short session id, its label when it has one, its worktree path, and its branch — followed by the reason the child needs it, stated plainly: the child's own worktree is branched from the base and therefore does not contain that session's uncommitted or unmerged work. The child reads across when its task needs to.

The instruction is read-only. Another session's worktree is a live tree with an owner mid-edit; writing into it races that owner and lands changes no branch of the writer's will ever carry.

Same family rule as the other injections: a POINTER, never a body — the launch prompt stays small and the agent always reads the live file. And fail-quiet by absence, the rule spec-pointer already follows: no parent (a human launching from a plain shell), or a parent whose record carries no worktree, appends nothing.

It composes with spec-pointer rather than replacing it. A dispatch naming a node that exists in the base tree still gets its own spec path first; a dispatch whose node lives only on the spawner's branch gets the spawner line alone — not the path it wanted, but enough for the agent to find it. The clause is a pure function of the spawner's record, so what the child is told is exactly what the board shows about its parent.