ADR 0006 — ID-anchored URLs, path-key fallback, never title-derived

Status: Accepted

Context

OBSERVED: the current slug is slugify(id ? id-title : title). For 68 of 117 authored documents there is no id, so the URL is a function of the title and changes whenever the title is edited.

Decision

/a/{id} for the 569 artifacts with a declared id. /s/{path-key} — a hash of the repository-relative source path — for the rest. Never title-derived. /collections/{facet}/{value}/ preserved verbatim. All legacy URLs redirected, enforced by a blocking build gate.

Evidence

OBSERVED: 49 authored + 520 frontier ids, all unique, zero duplicates. OBSERVED: 175 collection pages are the only navigation that currently works.

Alternatives

Invent ids for id-less documents — rejected by §28. Keep title slugs — rejected: demonstrably unstable.

Consequences

Two URL classes to explain. The UI marks path-key artifacts as lacking a declared id, which doubles as an authoring nudge.

Reversibility

Low — redirects absorb future changes.