> ## Documentation Index > Fetch the complete documentation index at: https://docs.helix-db.com/llms.txt > Use this file to discover all available pages before exploring further. # Limits
Reference
> For the complete documentation index optimized for AI agents, see [llms.txt](/llms.txt). Current constraints and practical limits. These reflect the current implementation, not fundamental architectural boundaries. ## Data Model | Limit | Value | | ---------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Node and edge ID range | 64-bit unsigned integer (max 2^64 - 1); JSON responses encode lifecycle identifiers as decimal strings | | Property value types | boolean, integer, float, string, bytes, typed primitive arrays, generic arrays, and objects | | Nested structures | Stored object/array values are supported. Dotted-path lookup such as `metadata.externalID` works in scan-time filters, expressions, projections, `values`, filtered `valueMap`, and fallback ordering. Arrays are opaque; there is no array-index path syntax. | | Reserved property keys | `$label` (used for label-based filtering and label-scoped secondary, vector, and text indexes) | ## Vector Indexes | Limit | Value | | ------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------- | | Scope | Node and edge properties | | Supported property types | Numeric array properties (`float32[]`, `float64[]`, `int64[]`) normalized to `float32` for indexing | | Tenant partitioning | Optional by configured tenant property name. Tenant-scoped searches require a tenant value. Unknown tenant partitions return no results. | | Dimension matching | Vectors must exactly match the configured index dimension | | Distance metrics | cosine, euclidean, manhattan | | Search type | Approximate nearest neighbor (ANN) | | Restricted search | Final membership is the exact current traversal stream; ranking may still use approximate index structures | ## Text Indexes | Limit | Value | | ------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Scope | Node and edge properties | | Supported property types | Top-level `String` and `StringArray` properties. Nested object fields are not flattened for BM25. | | Unsupported values | `null` and non-string values are rejected | | Analyzer config | Preset analyzers: `standard`, `standard_stem_en`, `whitespace_lowercase` | | Term positions | Optional | | Tenant partitioning | Optional. Tenant-partitioned text indexes currently require the partition property name to be `tenant_id`, and tenant-scoped searches require a tenant value. | ## Secondary Indexes | Limit | Value | | ---------------- | ---------------------------------------------------------------------------------------------------------- | | Equality indexes | Supported on top-level node and edge properties. Nested dotted paths are scan-only in V1. | | Range indexes | Supported on top-level numeric and string properties. Nested dotted paths are scan-only in V1. | | Encoding | Range indexes use lexicographic string encoding. Values must be encoded consistently for correct ordering. | ## Queries | Limit | Value | | ----------------- | ---------------------------------------------------------------------------------- | | Query model | Dynamic queries | | Query language | SDK DSLs or dynamic JSON AST | | Transaction scope | One transaction per query invocation | | Request envelope | One `read` or `write` operation-tree batch with named entries and explicit returns | ## Index lifecycle | Limit | Value | | ---------------- | --------------------------------------------------------------------------------- | | Activation | Asynchronous and atomic after scan, catch-up, and validation | | Progress | Monotonic entity/byte/operation counters; no percentage or total-work estimate | | Controls | Poll all operations; retry blocked operations; abort eligible constructing builds | | Memory reporting | Cache and batch budgets do not constitute a hard process-RSS cap | ## Embedded runtime | Limit | Value | | ------------------- | ------------------------------------------------------- | | Storage sources | In-memory, local disk, and S3-compatible object storage | | Handle modes | Writer or read-only | | Server options | Gateway headers and routing options are rejected | | Packaging | Install the SDK and its embedded runtime package | | Cache configuration | Fixed when the handle opens |