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+---
+bc-version: [all]
+domain: architecture
+keywords: [bcquality, knowledge-layer, microsoft, community, custom, session-start, consumption]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# Unconsumed BCQuality layers must be declared
+
+## Description
+
+BCQuality knowledge is organized in three layers — `microsoft/`, `community/`,
+`custom/` — and BCQuality's own documentation states all three are enabled by
+default when an agent consumes the repo. Tooling that builds a local cache or
+a session-start briefing from BCQuality can end up wiring only one layer
+(typically `custom/`, because it is small enough to preload in full) while
+silently never touching the other two. Nothing errors, nothing warns — the
+session proceeds under the impression that BCQuality is fully consulted when
+only a fraction of it actually is.
+
+## Best Practice
+
+Any component that fetches, caches, or reads BCQuality knowledge on behalf of
+an agent must state explicitly which layers it covers, next to the fetch logic
+itself (e.g. in the CLAUDE.md instruction or the agent file's Source section) —
+not left to be inferred from reading the code. A layer excluded because of
+scale (a large layer unsuited to full preload) requires either a filtered or
+on-demand retrieval path, or an explicit written note that the layer is out of
+scope for that tooling.
+
+## Anti Pattern
+
+Wiring a knowledge cache to one layer's fetch filter and describing the result
+in prose as "BCQuality knowledge" without naming which layers are actually
+included. This creates the false impression that the full rulebook — including
+Microsoft's official guidance — informs every session, when in fact only the
+custom layer does.