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CEO Plan: v0.38 Schema Packs — Bring Your Own Shape

Generated by /plan-ceo-review on 2026-05-19 Branch: garrytan/houston-v1 | Mode: EXPANSION Repo: thebuildceo/modusbrain

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Definitions (terms used throughout)

• Primitive — a named bundle of (default link verbs, default frontmatter fields, expert-routing flag, enrichment rubric slot). Five built-in: entity, media, temporal, annotation, concept. A pack type extends one primitive by name, inheriting its defaults, then optionally overriding specific fields. Not a table shape, not a schema in the SQL sense — a behavioral template the engine consults at inference and search time.
• Alias closure — for read paths, when a pack declares type researcher aliases base type person, queries for researcher expand the WHERE clause to type IN ('researcher','person', + any other type aliasing person). The closure is computed once at pack load, cached on the pack object, and inlined into search SQL. Aliasing is one-directional (researcher → person; querying person does NOT surface researcher rows unless the inverse is declared).
• Pack resolution chain (7 tiers) — extends model-config’s 6-tier pattern. Order: (1) per-call schema_pack opt, (2) MODUSBRAIN_SCHEMA_PACK env, (3) per-source --source <id> override via DB config key schema_pack:source:<id>, (4) brain-wide DB config key schema_pack, (5) modusbrain.yml schema: section, (6) ~/.modusbrain/config.json schema_pack, (7) default gbrain-base. Tier 3 is the new tier introduced in v0.38; tiers 1, 2, 4-7 mirror existing patterns.

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Vision

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10x Check

The plan as accepted ships a self-EXPANDING engine, not just a self-describing one. The differences from the baseline plan:

• The brain watches what you create and proposes schema refinements you didn’t think to ask for (schema suggest)
• Schema is per-source (ISOLATED reads), so ~/git/brain and ~/git/zion-brain hold different mental models in the same engine without renames. Cross-source federated reads still see per-source packs in isolation — a query joining results across mounts does NOT compute a closure across both packs. Federation (closure across mounts) is explicitly deferred to v0.39.
• The pack is inspectable: ASCII graph, plain-English explanation, consistency lint against actual content
• First unknown-type write asks “Add to pack?” with a primitive inference, instead of silently logging
• Schema packs distribute as .modusbrain-schema tarballs through the v0.37 skillpack pipeline; skillpacks rename to .modusbrain-skillpack for symmetry. Community schema packs propagate the same way community skillpacks do.

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Platonic Ideal

A new user clones modusbrain and types modusbrain init. Within 30 seconds modusbrain has read their existing markdown anywhere on disk, proposed a schema matching their organic shape, asked 3-5 yes/no questions to refine, and the brain is live. They never author YAML unless they want to. They can publish their pack as a .modusbrain-schema tarball for anyone to install and fork. The 12-month state: modusbrain init runs schema detect automatically, proposes a primitive structure, and 90% of users never see the manifest format. The 10% who want to customize see a clean YAML they can edit. Community packs cover the long tail of domains.

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Scope Decisions

Total budget: revised 9-11 weeks (vs ~6.5-7 initial estimate; spec review surfaced LLM prompt-tuning loops for schema suggest, primitive-inference heuristics for auto-prompt, 7-tier × federated- read interaction edges, full rename-migration surface, and 400-600 test cases at v0.36/v0.37 scope precedent). If budget pressure emerges, the safest cuts in order are: D5 auto-prompt (~2 days), D4 inspect triad (~2 days), reduce examples 7→3 (~3 days), defer suggest LLM polish to v0.38.1 (~1 week).

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Accepted Scope (added to this plan)

• Engine layer: gbrain-base universal starter pack; 5 composable primitives (entity, media, temporal, annotation, concept); alias closure for read paths; lenient-by-default with audit for write paths; strict mode opt-in.
• Detect layer: modusbrain schema detect SQL-driven heuristic clustering proposing a pack manifest matching brain shape.
• Suggest layer: modusbrain schema suggest LLM-powered refinement via gateway.chat() over a bounded sample.
• Inspect layer: modusbrain schema graph (ASCII viz), modusbrain schema lint (consistency check), modusbrain schema explain <type> (plain English).
• Author layer: modusbrain schema init/use/fork/edit/validate/ diff/review-candidates CLI.
• Source layer: per-source schema-pack resolution; pack resolution gets a 7th tier (per-source override before per-brain); --source <id> flag on every relevant command.
• Auto-prompt layer: TTY-gated interrupt on first unknown-type put_page with primitive inference; per-type “always silent” escape hatch.
• Distribution layer: .modusbrain-schema tarball format; rename skillpacks to .modusbrain-skillpack; v0.37 skillpack pipeline parameterized on artifact type (manifest discriminator drives type-specific validation); both extensions accepted on install for back-compat.
• Examples: 7 example packs in-tree (minimal, person-first, media-archive, temporal-archive, research-notebook, founder-ops, personal-archive) explicitly framed as sketches not products.
• gbrain-base: byte-for-byte reproduces today’s hardcoded behavior so existing brains see zero change after upgrade.
• Migrations: v76 drops takes.kind CHECK constraint; validation moves to runtime against active pack’s declared kinds.
• Doctor checks: schema_pack_active, schema_pack_consistency, per-source pack drift.
• Engine refactor coverage: the v0.38 plan parameterizes EVERY hardcoded type-coupling site listed in the original exploration, not just takes.kind. Concretely: inferType path-prefix table, inferLinkType regex bank, FRONTMATTER_FIELD_OVERRIDES table, find_experts SQL (type IN (…)), whoknows DEFAULT_TYPES, enrichment-service person/company restriction, completeness.ts rubric map, dream-cycle entity-type prompts. gbrain-base reproduces today’s values for each.
• Cache + rollback story:
  • query_cache.knobs_hash (v0.32.3 column) folds schema_pack name + version into the hash so a cache row written under vc is unreachable when research-state is active. Cross- pack contamination structurally impossible.
  • eval_candidates rows (v0.25.0) gain a schema_pack column so modusbrain eval replay reproduces the same retrieval space. Migration v77 adds the column NULL-tolerant; pre-v0.38 rows fall back to active pack during replay.
  • HNSW indexes are pack-agnostic (vector columns don’t change shape across packs); no reindex needed on pack switch.
  • Rollback: every modusbrain schema use operation writes the previous pack name to ~/.modusbrain/schema-pack-history.jsonl so modusbrain schema use --previous is one keystroke. Strict- mode failures on switch surface the offending pages with paste-ready “rename type to X” hints before any data mutation runs. Soft-deletes from autopilot purge are NOT triggered by pack changes.
• Test budget: ~400-600 cases across unit + e2e per the v0.36/v0.37 precedent. Specifically: ~150 cases for engine layer
  • alias closure, ~50 for detect heuristic accuracy, ~50 for suggest LLM prompts (hermetic via stubbed gateway), ~30 for per- source resolution × 7-tier matrix, ~40 for auto-prompt UX states, ~30 for inspect triad output stability, ~30 for tarball type-detection + parameterized install, ~50 for migration v76 + v77 + bootstrap parity, ~50 for examples × byte-for-byte gbrain-base equivalence regression. gbrain-base byte-for-byte parity is a CI gate, not a hope — pinned by test/regressions/gbrain-base-equivalence.test.ts asserting the pre-v0.38 hardcoded behavior reproduces from the pack-driven paths on a fixture brain.

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Deferred to TODOS.md (v0.39+)

• Live-brain fork-from <brain-path> (rejected for privacy; revisit if a sandboxed schema-only extraction path is designed)
• Per-source pack FEDERATION across mounts (a query crossing multiple sources can use closure over each source’s schema; right now per-source is isolated reads only)
• Schema versioning + semver compatibility checks between pack versions
• Skillpack ↔ schema-pack cross-reference (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)
• Schema diff in PR review (rendering pack changes as human-readable diffs for community pack PRs)

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Reviewer Concerns (from spec review loop, partially addressed)

• Quality score on first pass: 6.5/10. Issues addressed in this revision: definitions block (primitive, alias closure, 7-tier resolution chain), per-source isolation vs federation contradiction clarified, skillpack extension framing changed from rename to expansion, full hardcoded-site coverage enumerated, cache + rollback story added, test budget enumerated, budget revised to 9-11 weeks honestly.
• Issues NOT fully addressed, surfaced for the 11-section review:
  • schema suggest LLM prompt-tuning iteration budget remains a range estimate, not a measured number. The 11-section review should pin a specific eval fixture set (size + diversity) and a target accuracy threshold before code lands.
  • 7-tier resolution × v0.34.1 federated_read OAuth scoping has edge cases at the intersection that the 11-section review must enumerate (specifically: an OAuth client with read scope across federated sources but no source-specific pack override — which pack drives the alias closure for cross-source queries?).
  • The 7→3 example pack reduction is a real cut consideration. The 11-section review should decide whether 7 examples is the right number or whether 3 + community-derived is more honest.

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Cathedral risks worth surfacing in 11-section review

1. The 7-week budget vs 4-week original ask. If pressure emerges, D5 (auto-prompt) and D4 (inspect triad) are the safest cuts.
2. v0.37 skillpack registry currently has zero published packs. The .modusbrain-schema rename and tarball reuse doubles down on a distribution layer with no usage signal.
3. Per-source pack resolution adds a 7th tier to the resolution chain. The model-config 6-tier pattern is already cognitively dense; tier 7 is an inflection point.
4. schema suggest introduces ongoing LLM cost per invocation. Bounded by sampling, but sets a precedent for “modusbrain commands that cost money.”
5. Auto-prompt UX is novel. TTY gate + per-type silencing helps, but bulk-import flows could hit unexpected interruption patterns.