Invitation — history

The dated record of how Invitation got here, moved out of the spec on 2026-10-20 because a reader does not need it to use the spec today. The spec keeps every section spec-format.md requires and its Deleted: tombstones; everything smaller is in git log -- atoms/invitation.md.

Decisions

Entries that record a migration rather than a turn the pattern took.

• 2026-09-13 — The window boundary is declared once as a window reading, in the same two-member shape Provisional Commitment uses. Chose: live

  lapsed, with the boundary instant declared onto the lapsed side, cited by the three resolving-write guards and by the effective-status projection. Over: repeating the comparison at each guard, which is how the prose carried it. Because: a spec pays for a proposition once (GRACE-lang Authority 3), and the arithmetic belongs in the declaration rather than in a rule (Hard invariant 24). The two atoms name the members differently — open there, live here — because the record differs; the shape being identical across two independent specs is a new instance of the absence-as-nonexistence class the grammar’s watch list counts, and is flagged rather than unified, since nothing yet says a shared reading should have one owner.

• 2026-09-13 — The family is resolving write, not resolving action, and the difference from Provisional Commitment is meant. Chose: resolving write — [Accept], [Decline], [Revoke]. Over: resolving action, which is the name the same concept carries one atom over. Because: this atom has a [Read], so action would include a surface that resolves nothing and writes nothing, and the whole of the derived-expiry posture is that reading and writing are different things here. Provisional Commitment has no read, so nothing there needs the narrower word. The names diverge because the records do; a reader crossing between them should not assume the drift is carelessness (council read 39).

Migration notes

• 2026-09-13 — Invariant 1.2, tombstoned as a rule that could not bind. A draft of the migration carried a second rule — an admitted resolving write MUST NOT change a resolution field the write found — and it could not bind. An admitted resolving write runs only on a pending invitation (Operation 16 refuses every other case), and a pending invitation carries no resolution field (State 6), so the set the rule quantified over is empty at every reachable state. Same class as the resource return Provisional Commitment re-homed one atom earlier: a MUST that cannot be violated is decoration, and the cure is to find the rule that already makes it true rather than to keep a second copy that cannot fail (council read 39).