Decision docs

Four document types that sit around a single decision, separated by what they do to it. That is the whole discriminator, and it is what keeps the family from collapsing into one type with four names.

Type	What it does to the decision
Spike Report	Investigates the question that precedes it
RFC	Proposes it
ADR	Records it, once taken
SDD	Describes the design that implements it

Membership is decided by a written contract, not by resemblance

Each family carries a contract with an exclusion clause - the sentence written to test a candidate. When a family’s role inventory and its exclusion clause disagree about whether something belongs, the exclusion clause governs. That is a recorded decision, not a convention, and it was made because a candidate type once satisfied one and failed the other.

Bundles in this family

Bundle pages are generated from the library’s own manifest. They arrive with the generator; this page lists none by hand.

What admission costs

A type does not join this family because it seems to fit. It has to clear an admission test: at least one named source that publishes the document as a document. One type was refused on its own evidence after a full research pass found none - and the refusal was recorded with the same rigor as an acceptance, because a library that only documents its inclusions is telling you half of what it knows.