A schema pack tells gbrain what shape your brain takes — which directories exist, what types live in them, how the agent should infer types from paths, and which link verbs connect what to what. The schema pack is the dynamic, always-consulted artifact every skill reads when filing, querying, or routing experts. It is the single source of truth for "what's in your brain."
The v0.39.0.0 wave shipped a full schema-pack cathedral. This doc is the
user-facing reference; for implementation details see
docs/designs/V038_SCHEMA_PACKS.md (CEO plan) and the engine layer in
src/core/schema-pack/.
Two bundled packs:
-
gbrain-base(default) — reproduces pre-v0.38 hardcoded behavior byte-for-byte. Existing brains see zero behavior change after upgrade. Covers: person, company, deal, meeting, project, place, concept, writing, analysis, guide, hardware, architecture, etc. (the originalALL_PAGE_TYPESlist). -
gbrain-recommended— extendsgbrain-basewith the 13 additional directories described indocs/GBRAIN_RECOMMENDED_SCHEMA.md: deal, meeting, concept, project, source, daily, personal, civic, original, place, trip, conversation, writing. If you like the documented operational-brain pattern, activate this with:gbrain schema use gbrain-recommended
Plus user-installed packs at ~/.gbrain/schema-packs/<name>/pack.yaml
that you author with gbrain schema init or gbrain schema fork.
Five inspection verbs (shipped in v0.38):
gbrain schema active # show resolved pack + which tier set it
gbrain schema list # list bundled + installed packs
gbrain schema show # pretty-print the active pack
gbrain schema validate # validate a manifest's shape
gbrain schema use <pack> # activate a pack (writes ~/.gbrain/config.json)Eight authoring + discovery verbs (shipped in v0.39):
gbrain schema detect # propose types matching brain shape
gbrain schema suggest # LLM-refined proposals on top of detect
gbrain schema review-candidates # promote / rename / ignore candidates
gbrain schema review-orphans # surface pages with no matching type
gbrain schema init <name> # scaffold a stub pack (experimental)
gbrain schema fork <a> <b> # copy + rename a pack (experimental)
gbrain schema edit <name> # surface the pack path (experimental)
gbrain schema diff <a> <b> # set-diff two packs (experimental)
gbrain schema graph # ASCII type listing (experimental)
gbrain schema lint # flag duplicates + missing prefixes
gbrain schema explain <type> # plain-English type description (experimental)
gbrain schema downgrade --to <p> # restore previous pack (recovery)
gbrain schema usage --since 30d # per-verb invocation counts (D14 telemetry)The verbs marked experimental are demand-gated per D14: their usage is
tracked via T15's schema-events audit, and v0.40+ retro decides whether
to deprecate any that stay <5% usage.
When the engine decides "which pack is active for this query?", it walks this chain top-down. First match wins.
| Tier | Source | Notes |
|---|---|---|
| 1 | Per-call schema_pack opt |
CLI only (ctx.remote === false); MCP rejected. |
| 2 | GBRAIN_SCHEMA_PACK env |
Process-scope override. |
| 3 | Per-source DB config key schema_pack:source:<id> |
New in v0.38. |
| 4 | Brain-wide DB config key schema_pack |
|
| 5 | gbrain.yml schema: section |
Repo-checked. |
| 6 | ~/.gbrain/config.json schema_pack field |
What gbrain schema use writes. |
| 7 | Default: gbrain-base |
Always present. |
Every read + write path consults the active pack at runtime:
parseMarkdowninfers pagetypefrom path prefixes declared in the active pack (page_types[].path_prefixes). Without an active pack threaded, falls back to the legacy hardcodedinferType()so the byte-for-byte parity gate stays green.whoknows/find_expertsscopes candidates toexpert_routing: truetypes in the active pack.extract_factsruns only onextractable: truetypes.enrichment-serviceroutes person/company enrichment based on the pack's primitive declarations.- Search hybrid cache (
knobsHash) folds in pack name + version (v0.39 T21). A cache row written under pack A is unreachable when pack B is active. Cross-pack contamination is structurally impossible.
Persona A (Notion refugee) installs gbrain, imports her exports, and the
brain looks unfamiliar — the default gbrain-base pack expects
people/, companies/, etc., but her files live under Projects/,
Reading/, Daily Notes/. The friction signal fires in two places:
- Import warn (T7): the end of
gbrain importprints[schema] X of Y pages (Z%) have no type matching the active schema pack. Run gbrain schema detect to propose a pack matching your content shape. gbrain doctorschema_pack_consistency check keeps surfacing the warning persistently after the import session ends.
She runs the magical moment:
gbrain schema detect # heuristic clustering on her actual shape
gbrain schema suggest # LLM-refined proposals
gbrain schema review-candidates # human gate on promotion
gbrain schema review-candidates --apply Projects/ # acceptThe agent (via the new EIIRP skill) automates phases 1-3 of this for any significant work session. The brain's schema becomes a living artifact the agent maintains, not a hardcoded ceremony the user authors.
gbrain schema init my-pack # scaffolds ~/.gbrain/schema-packs/my-pack/pack.yaml
$EDITOR ~/.gbrain/schema-packs/my-pack/pack.yaml
gbrain schema validate my-pack # check shape
gbrain schema use my-pack # activate
gbrain schema active # confirmA minimal pack:
api_version: gbrain-schema-pack-v1
name: my-pack
version: 0.0.1
gbrain_min_version: 0.39.0
extends: gbrain-base # inherits everything from base; add overrides below
description: |
My personal pack.
page_types:
- name: project-x
primitive: entity
path_prefixes:
- Projects/
aliases: []
extractable: false
expert_routing: false
# Add more types here. Each maps a path prefix to a primitive +
# opt-in flags. See src/core/schema-pack/base/gbrain-recommended.yaml
# for a worked example.
link_types: []
takes_kinds: [fact, take, bet, hunch]
borrow_from: []
frontmatter_links: []
enrichable_types: []
filing_rules: []The single-PR cathedral is hard to revert atomically. Per codex finding
#4 from plan-eng-review, T20 ships gbrain schema downgrade to restore
the active-pack config field:
gbrain schema downgrade --to gbrain-base
# OR auto-detect previous from ~/.gbrain/schema-pack-history.jsonl:
gbrain schema downgradeCode revert alone is NOT sufficient. The full revert procedure:
git revert <merge-commit>— restores the code.gbrain schema downgrade --to gbrain-base— restores config.- (Optional)
gbrain pages purge-deleted --older-than 0h— drops v0.39-typed pages that no longer have a matching type in the active pack.
The cache + eval rows that pack-aware code wrote are isolated by the
knobsHash pack-folding (T21) — they become unreachable under the
restored pack so no eviction is needed.
.gbrain-schema tarballs ride the same v0.37 skillpack pipeline as
.gbrain-skillpack tarballs (T14 artifact abstraction). The
discriminator is api_version in the manifest:
gbrain-schema-pack-v1→ schemapackgbrain-skillpack-v1→ skillpack
Both install via the same scaffold + copy path; install targets are
~/.gbrain/schema-packs/<name>/ and ~/.gbrain/skillpacks/<name>/
respectively.
Publication to the public registries (garrytan/gbrain-schema-registry,
garrytan/gbrain-skillpack-registry) follows the same publish-as-PR
workflow as v0.37 skillpack publishing.
- Per-source pack federation across mounts. A query crossing multiple
sources currently rejects with
permission_deniedwhen those sources have divergent active packs (T19 + codex finding #2). The v0.40+ work computes a true per-source closure via the existingbuildSourceClosureCteengine surface. extendschain semver compatibility checks between pack versions.skillpack ↔ schemapackcross-reference declarations — a skillpack can declare "I work best with these primitives present in your pack."- Live schema migration helpers — when you add a type, auto-suggest backfill of existing pages.
- Authoring vs derivation thesis reframe (D14). v0.39.0.0 ships the full 11-verb cathedral with 6 verbs marked experimental-tier. v0.40+ retro reads T23 usage telemetry to decide which to deprecate.
See TODOS.md v0.40+ section for the full deferred list.