Replace the single ASCII stack in docs/architecture.md with a hierarchy of
Mermaid diagrams that show the system from external context down to the
component level. Add an on-disk layout diagram in docs/storage.md and two
sequence diagrams (read query, mutation) in docs/execution.md so readers
can navigate from "what is OmniGraph" to "how does a query run" without
opening source.
Static structure (docs/architecture.md):
- System context — agents/clients, embedding providers, Cedar, object store.
- Layer view — eight-layer stack with L1 (Lance) / L2 (OmniGraph) styling
via classDef, replacing the pre-existing ASCII art.
- Component zoom-ins — compiler, engine, storage trait, index lifecycle,
server/CLI. Each zoom-in cites file:line entry points.
Aspirational shapes (storage trait, full reconciler) are visually marked
and pointed at the relevant invariants.md section so readers see the
intended seam without thinking it's already implemented.
On-disk layout (docs/storage.md):
- Tree from repo URI through __manifest, nodes/, edges/, _graph_commits.lance,
_graph_runs.lance, _refs/branches/ down into Lance's per-dataset
internals (_versions/, data/, _indices/, _refs/, _transactions/).
- Annotated with the actual filenames so readers can `ls` the same paths.
- Slots in below the existing __manifest CAS / OCC / migration prose; does
not move or rewrite that content.
Runtime flows (docs/execution.md):
- Read flow sequence: client → Omnigraph::query → typecheck → lower →
execute_query → table_store → Lance scanner → RecordBatch stream.
- Mutation flow sequence: Omnigraph::mutate → resolve literals →
Lance write op (Append / merge_insert) → ManifestRepo::commit →
__manifest upsert.
- Both diagrams are followed by a "Code paths" block with verified
file:line citations so readers can navigate from diagram element to
source in one step.
Conventions established (this is the first Mermaid in the repo):
- L1 = orange (#fef3e8), L2 = blue (#e8f4fd), aspirational = dashed.
- Diagram size cap ~9 elements; more detail goes in a sub-diagram.
- Diagrams paired with prose; code-path citations follow each diagram.
- Consistent vocabulary across diagrams: frontend / compiler / engine /
storage trait / Lance / object store. No accidental synonyms.
Subsequent PRs will add flow diagrams for schema apply, branch + merge,
run isolation, index reconcile, and the embedding pipeline in the same
conventions.
The on-disk shape of `__manifest` is reconciled with the binary via a single
stamp + dispatcher in `db/manifest/migrations.rs`:
- `INTERNAL_MANIFEST_SCHEMA_VERSION = 2` declares the shape this binary writes.
- The on-disk stamp `omnigraph:internal_schema_version` lives in the manifest
dataset's schema-level metadata (Lance `update_schema_metadata`).
- `migrate_internal_schema(&mut dataset)` walks `match`-arm steps forward from
the on-disk stamp until it matches the binary, then returns. Idempotent.
- `init_manifest_repo` stamps the current version at creation; the publisher's
open-for-write path runs pending migrations before reading state. Reads
stay side-effect-free.
- Forward-version protection: a stamp higher than the binary's known version
triggers a clear "upgrade omnigraph first" error so an old binary cannot
clobber a newer schema.
Self-heals existing pre-MR-766 deployments by auto-applying the v1→v2 step:
the `lance-schema:unenforced-primary-key` annotation on `__manifest.object_id`
that engages Lance's row-level CAS at commit time. New repos created via
`init` are stamped at v2 immediately and don't need migration.
Adding a future on-disk shape change is one constant bump, one match arm in
`migrate_internal_schema`, and one test — no new branches in unrelated code
paths. Code outside the migration module never inspects the stamp.
New tests in `manifest/tests.rs`:
- `test_init_stamps_internal_schema_version`
- `test_publish_migrates_pre_stamp_manifest_to_current_version`
- `test_publish_rejects_manifest_stamped_at_future_version`
Docs: `docs/storage.md`, `docs/maintenance.md`, `docs/constants.md` updated
per the AGENTS.md maintenance contract.
- storage.md: document the row-level CAS annotation on `__manifest.object_id`
and the `expected_table_versions` OCC contract on `ManifestBatchPublisher::publish`.
- errors.md: list `ManifestConflictDetails` and its variants alongside `ManifestError`.
- constants.md: add `PUBLISHER_RETRY_BUDGET = 5`.
Per AGENTS.md "Maintenance contract": new schema construct, new constant, and
new typed error shape all need to ship with the source change.
All eight comments verified against source and applied:
- AGENTS.md: pull @docs/{invariants,lance,testing}.md imports out of
the markdown blockquote. Claude Code's @-import parser expects @ at
column 0; the leading "> " of a blockquote silently broke
recognition, so the claimed auto-include did nothing. (Cursor,
Medium severity.)
- docs/cli-reference.md: command-family count 13 → 17. The current
enum Command in crates/omnigraph-cli/src/main.rs has 17 top-level
variants. (cubic P2.)
- docs/ci.md: Homebrew tap update is a regular `git push`, not a
force-push (release.yml:117 is `git push origin HEAD:main`). (cubic
P2.)
- docs/errors.md: add the Storage variant to the NanoError list — it
exists at error.rs:88-89 but the doc enumerated only 10 of 11.
(cubic P2.)
- docs/storage.md: clarify tombstone semantics. There is no
tombstone_version column; state.rs:180 reads the tombstone version
from the table_version column on rows where object_type =
table_tombstone. (cubic P2.)
- docs/branches-commits.md: split the GraphCommit pseudo-struct from
the underlying storage. actor_id is joined in-memory from
_graph_commit_actors.lance, not a column on _graph_commits.lance.
(cubic P2.)
- docs/schema-language.md: rename IR_VERSION to SCHEMA_IR_VERSION to
match the actual constant name in catalog/schema_ir.rs:11.
(cubic P3.)
- docs/testing.md: engine integration test count 16 → 15 (matches
`ls crates/omnigraph/tests/*.rs`). (cubic P3.)
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Splits the 990-line AGENTS.md into a 184-line map (architecture,
where-to-find index, always-on invariants, capability matrix,
maintenance contract) plus 18 new docs/*.md files holding the deep
content per topic (storage, schema and query languages, indexes,
embeddings, branches/commits, runs, merge, changes, execution, policy,
server, CLI reference, audit, errors, CI, constants, v0.3.1 notes).
Adds scripts/check-agents-md.sh and a check_agents_md CI job that
verifies every docs/ link in AGENTS.md resolves and every doc in the
canonical set is linked. CLAUDE.md remains a symlink to AGENTS.md.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
