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Curates the Lance documentation site (lance.org) into a problem-domain index so agents fetch the right page when working on Lance-touching code instead of guessing or grepping our codebase. Organized by topic: storage format & file layout, branching/tags/time travel, indexes (scalar + system + vector), reads/writes, schema evolution, object store, data types, performance, compaction, DataFusion integration, SDK reference, plus quick-starts and the upstream AGENTS.md. Skips ~200 irrelevant URLs from the upstream sitemap (Namespace REST API model surface, Spark/Trino/Databricks/etc. integrations, Python/Ray/HuggingFace docs, community pages) since omnigraph is Rust-only and doesn't run a Lance Namespace catalog. AGENTS.md surfaces it in the topic index and adds a directive: "when you hit a Lance-shaped problem, consult docs/lance.md and fetch the upstream URL before guessing." Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Lance Docs Index (for OmniGraph agents)
OmniGraph sits on top of Lance. Many problems — index lifecycle, branching, transactions, fragments, compaction, vector/FTS internals — are answered upstream in Lance's docs, not in this repo.
This file is the curated entry point. When you hit a Lance-shaped problem, find the matching topic below and fetch the listed URL(s) before guessing. Don't grep our codebase for behavior that is documented authoritatively in Lance.
Base URL: https://lance.org. Use WebFetch (or your tool's equivalent) on the full URLs. Keep this index curated to relevant material — the upstream sitemap has hundreds of URLs (notably the Namespace REST API model surface, Spark/Trino/Databricks integrations) that we don't use.
Substrate boundary check. Before fetching, recall docs/invariants.md §I: if Lance already does the thing, we don't reimplement it. The most common reason to read these docs is to confirm a substrate behavior, not to learn what to clone.
Quick-start (read these once per project)
| Read when | URL |
|---|---|
| Onboarding to Lance — concepts in 10 min | https://lance.org/quickstart/ |
| Onboarding to vector search | https://lance.org/quickstart/vector-search/ |
| Onboarding to full-text search | https://lance.org/quickstart/full-text-search/ |
| Onboarding to versioning / time travel | https://lance.org/quickstart/versioning/ |
| Lance's own AGENTS.md (its agent guide) | https://lance.org/format/AGENTS/ |
By problem domain
Storage format & file layout
Touching db/manifest, fragment lifecycle, dataset reconstruction, or anything that reads/writes raw Lance state.
| Topic | URL |
|---|---|
| Lance file format overview | https://lance.org/format/ |
| File-level format spec | https://lance.org/format/file/ |
| File encoding | https://lance.org/format/file/encoding/ |
| File-level versioning | https://lance.org/format/file/versioning/ |
| Table layout (fragments, manifest) | https://lance.org/format/table/layout/ |
| Table schema metadata | https://lance.org/format/table/schema/ |
| Table-level versioning | https://lance.org/format/table/versioning/ |
| Transactions (commit semantics, conflict types) | https://lance.org/format/table/transaction/ |
| MemWAL (durability story) | https://lance.org/format/table/mem_wal/ |
| Row-ID lineage (stable row IDs) | https://lance.org/format/table/row_id_lineage/ |
| Branches & tags (Lance native) | https://lance.org/format/table/branch_tag/ |
Branching / tags / time travel
Touching graph-level branches, snapshots, run isolation, the commit graph.
| Topic | URL |
|---|---|
| Branch & tag format | https://lance.org/format/table/branch_tag/ |
| Tags & branches operational guide | https://lance.org/guide/tags_and_branches/ |
| Versioning quick-start | https://lance.org/quickstart/versioning/ |
| Table-level versioning spec | https://lance.org/format/table/versioning/ |
Indexes
Adding/changing index types, fixing coverage, debugging FTS or vector recall, designing the reconciler.
Reads & writes
Touching the bulk loader, mutation execution, merge_insert, WriteMode selection.
| Topic | URL |
|---|---|
| Read-and-write guide | https://lance.org/guide/read_and_write/ |
| Distributed write | https://lance.org/guide/distributed_write/ |
| Rust example: write & read a dataset | https://lance.org/examples/rust/write_read_dataset/ |
Schema evolution
Touching apply_schema, the migration planner, additive evolution.
| Topic | URL |
|---|---|
| Data-evolution guide | https://lance.org/guide/data_evolution/ |
| Migration guide | https://lance.org/guide/migration/ |
Object store / S3
Touching storage.rs, S3-compatible backends (RustFS, MinIO), env vars.
| Topic | URL |
|---|---|
| Object-store guide | https://lance.org/guide/object_store/ |
Data types
Touching schema-language scalar mappings, blob columns, JSON, list columns.
| Topic | URL |
|---|---|
| Data types overview | https://lance.org/guide/data_types/ |
| Arrays / list types | https://lance.org/guide/arrays/ |
| Blobs (LargeBinary) | https://lance.org/guide/blob/ |
| JSON | https://lance.org/guide/json/ |
Performance & tuning
Optimizing scans, fragment counts, cache behavior, memory pool sizing.
| Topic | URL |
|---|---|
| Performance guide | https://lance.org/guide/performance/ |
Compaction & cleanup
Touching omnigraph optimize / cleanup, the underlying compact_files / cleanup_old_versions.
| Topic | URL |
|---|---|
Read-and-write guide (covers compact_files, cleanup_old_versions) |
https://lance.org/guide/read_and_write/ |
| Performance (compaction tradeoffs) | https://lance.org/guide/performance/ |
| Fragment-reuse index | https://lance.org/format/table/index/system/frag_reuse/ |
DataFusion integration
The runtime substrate that may carry our query execution. See docs/invariants.md §I.4: we don't rebuild relational machinery.
| Topic | URL |
|---|---|
| DataFusion integration | https://lance.org/integrations/datafusion/ |
SDK reference
Looking up a specific Rust API (signature, return type, error variant).
| Topic | URL |
|---|---|
| SDK docs landing | https://lance.org/sdk_docs/ |
What's not in this index (and why)
- Namespace REST API model surface (
/format/namespace/client/operations/models/...) — hundreds of REST schema docs for the Lance Namespace catalog API. Omnigraph does not run a Lance Namespace server, so these are not reachable from our problem space. - Spark / Trino / Databricks / Dataproc / Hive / Glue / Polaris / Iceberg / Unity / OneLake / Gravitino integrations — not part of OmniGraph's deployment surface.
- Python / TF / PyTorch / Hugging Face / Ray integrations — OmniGraph is Rust-only; Python notebooks aren't relevant.
- Community / governance / release / voting / PMC pages — meta, not technical.
If a future need pulls one of these into scope, add a row to the matching domain section above and link it from AGENTS.md's topic index.
Maintenance
When Lance ships a major release that changes any of the above (file format bump, new index type, transaction semantics change, new branching primitive), refresh this index in the same change as the omnigraph upgrade. Stale Lance pointers are worse than no pointers.