The 14-canonical-type DRY/MECE taxonomy shipped in v0.41.22. Predecessor
gbrain-base(24 types) stays bundled for back-compat; v0.42+ installs default togbrain-base-v2.
A production gbrain brain (186K pages) had accreted 94 distinct
pages.type values in 9 clusters of redundancy. The type system is
the foundation for schema packs, search filtering, extract behavior,
enrichment routing, and expert routing. When types are noisy, every
downstream feature degrades:
- Search filtering is ambiguous —
--type articlemisses 2.2K articles typed asmedia/article,sources/article, etc. - Enrichment routing is incomplete —
enrichable_typescould only list a few canonical types; 80+ legacy types meant most pages never got enriched. - Agent confusion — when ingesting a new article, should it be
article,media/article,sources/article, orsource/article? Four reasonable choices, none of them right. - Orphan inflation — 5,521 concept-redirect pages inflated orphan counts without adding knowledge value.
Issue #1479 catalogues the 9 clusters with exact counts. This doc is the response: a coherent 14-type taxonomy with subtypes/format/origin pushed to frontmatter, alias-table rows for redirects, real link-table rows for edge-shaped pages.
| Type | Primitive | What it holds | Examples |
|---|---|---|---|
person |
entity | People | Founders, partners, individuals |
company |
entity | Companies, products, orgs (subtype-distinguished) | Companies, YC-companies, products |
media |
media | Articles, videos, essays, books, podcasts (subtype-distinguished) | Substack posts, YouTube videos, books |
tweet |
media | Twitter posts (single/bundle/stub subtype) | Single tweets, threads, bundles |
social-digest |
temporal | Period-grouped social summaries (daily/monthly) | X account daily digests |
analysis |
media | Research + competitive intel | Market analysis, pricing analysis |
atom |
annotation | Knowledge units (extraction/manual/lore subtype) | Extracted facts, manual notes, lore |
concept |
concept | Ideas + reference pages | Wiki concepts |
source |
media | Transcripts, references | Interview transcripts |
deal |
temporal | Investment deals | Term sheets, investments |
email |
temporal | Email threads | Email correspondence |
slack |
temporal | Slack messages + threads | Slack conversations |
writing |
media | Original writing | Drafts, essays in progress |
project |
concept | Initiatives, workstreams | Internal projects |
note |
concept | Catch-all for one-offs (legacy_type preserved) | Memos, anecdotes, insights, etc. |
15 types total (14 canonical + note). The catch-all retype rule
binds any uncovered legacy type to note with
frontmatter.legacy_type = <original> preserved for rollback.
| Canonical | Subtype field | Values |
|---|---|---|
company |
subtype |
company / product / org |
media |
subtype |
video / article / essay / book / podcast / blog |
tweet |
subtype |
single / bundle / stub |
social-digest |
subtype |
daily / monthly |
atom |
subtype |
extraction / manual / lore |
subtype_field for retype rules is restricted to an allowlist:
{subtype, legacy_type, origin, format, kind, period, domain}. This
prevents third-party packs from injecting title, slug, or type
via mapping_rules (codex D9 security hardening).
gbrain onboard --check # surfaces pack_upgrade_available
↓
gbrain onboard --check --explain # per-cluster narrative dry-run
↓
gbrain jobs submit unify-types \ # PROTECTED + manual_only
--allow-protected \
--params '{"target_pack":"gbrain-base-v2"}'
↓
Handler runs 4 phases:
┌─────────────────────────────────────┐
│ Phase 1: Preflight + lock │ → gbrain-unify db-lock (60min TTL)
├─────────────────────────────────────┤
│ Phase 2: Retype explicit rules │ → chunked UPDATE 1000/batch
├─────────────────────────────────────┤
│ Phase 3: Retype catch-all sentinel │ → 'note' with legacy_type
├─────────────────────────────────────┤
│ Phase 4: Page-to-link conversions │ → insert links + soft-delete
├─────────────────────────────────────┤
│ Phase 5: Page-to-alias conversions │ → insert slug_aliases + soft-delete
├─────────────────────────────────────┤
│ Phase 6: Final sync (residual) │ → path-prefix typing
├─────────────────────────────────────┤
│ Phase 7: Flip active pack (D13) │ → engine.setConfig + saveConfig
├─────────────────────────────────────┤
│ Phase 8: Verify + celebrate │ → assert ≤16 types; stderr summary
└─────────────────────────────────────┘
↓
gbrain onboard --check # pack_upgrade_available cleared
# type_proliferation cleared
Every primitive ships with a documented rollback:
| Operation | Rollback |
|---|---|
| Retype | frontmatter.legacy_type = <original> preserved on every page (D8). One SQL UPDATE restores types: UPDATE pages SET type = frontmatter->>'legacy_type' WHERE frontmatter ? 'legacy_type'. |
| Page-to-link | Source page soft-deleted with 72h TTL. gbrain pages restore <slug> within 72h. Link row stays harmless if source restored. |
| Page-to-alias | Source page soft-deleted with 72h TTL. gbrain pages restore <slug> within 72h. Alias row stays harmless (or DELETE FROM slug_aliases WHERE alias_slug = <slug> to clean up). |
| Active-pack flip | gbrain schema use gbrain-base reverses the flip. |
The catch-all retype rule (from_type: '*unknown*') handles long-tail
types automatically — any page whose type isn't covered by an explicit
rule AND isn't a page_to_link / page_to_alias source gets retyped to
note with legacy_type preserved. Guarantees ≤16 distinct types
post-unify on ANY brain.
For brains with substantial custom types that deserve their own canonical
(e.g. researcher for an academic brain), the right move is:
- Fork gbrain-base-v2:
gbrain schema fork gbrain-base-v2 my-pack - Edit your fork to add page_types + mapping_rules covering your custom domain.
- Target your fork:
gbrain jobs submit unify-types --allow-protected --params '{"target_pack":"my-pack"}'
Your fork can also declare migration_from: {pack: gbrain-base-v2, version: "1.x"} to register itself as a successor — future agents
discovering your pack via pack_upgrade_available will offer the
migration.
The slug_aliases table IS the resolver (D15: codex outside voice —
don't rewrite body-text wikilinks; the alias table is the right
primitive). Wikilinks like [[old-redirect-slug]] keep working post-
unify because:
- The wikilink resolver short-circuits through
engine.resolveSlugWithAlias(slug, sourceId)BEFORE the existing fuzzy/prefix cascade. - The lookup queries
slug_aliasesfor any matching alias_slug in the provided source(s). - If found, returns the canonical_slug. The renderer then resolves the wikilink to the canonical page.
Multi-source ambiguity (same alias_slug in two registered sources)
emits a once-per-process multi_match stderr warning and returns the
first match by source array order. Federated reads pass the full
allowed-source array.
Post-unify, search results whose slug is a canonical_slug in
slug_aliases get a 1.05x score multiplier via the
applyAliasResolvedBoost post-fusion stage. Semantic intent: "user
explicitly disambiguated this as canonical, so it should outrank fuzzy
matches that hit aliases by accident."
SearchResult.alias_resolved_boost is stamped on touched results for
--explain formatter visibility. KNOBS_HASH_VERSION bumped 5→6 to
invalidate pre-v0.42 cache rows that don't reflect the new stage.
- Issue: garrytan#1479
- Pack file:
src/core/schema-pack/base/gbrain-base-v2.yaml - Pack-upgrade mechanism:
docs/architecture/pack-upgrade-mechanism.md - Migration handler:
src/core/schema-pack/unify-types-handler.ts - Onboard checks:
src/core/onboard/checks.ts - Skill:
skills/schema-unify/SKILL.md - Plan + decisions:
~/.claude/plans/system-instruction-you-are-working-transient-elephant.md