Enum SearchTier 

pub enum SearchTier {
    Instant,
    Dense,
    Fast,
    Deep,
    Auto,
}

Retrieval tier — selects the work the search engine does for a query.

Instant and Dense are single-retriever ablations (BM25-only and vector-only respectively), exposed mostly for the quality benchmark harness but also useful as product knobs when callers want a pure keyword or pure semantic search. Fast and Deep are the production hybrid tiers. Auto (the new default) routes per-query to the cheapest tier that’s likely to do the job, mirroring Exa’s auto philosophy.

Variants

Instant

FTS5 BM25 only. No model load, no vector index access.

Dense

Vector index only (binary-quantized Hamming KNN). Uses the dense embedder; primarily an ablation for quality benchmarks.

Fast

BM25 + dense + RRF fusion. Production hybrid tier.

Deep

Fast + cross-encoder reranking over the top-K fused candidates.

Auto

Inspect the query and route to the cheapest tier likely to answer it well: identifier-shaped short queries → Instant; long question-form queries (or [deep] prefix) → Deep; everything else → Fast. Default tier.

Trait Implementations

impl Clone for SearchTier

fn clone(&self) -> SearchTier

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SearchTier

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for SearchTier

fn default() -> SearchTier

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for SearchTier

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for SearchTier

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl FromStr for SearchTier

type Err = LexaError

The associated error which can be returned from parsing.

fn from_str(value: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl PartialEq for SearchTier

fn eq(&self, other: &SearchTier) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for SearchTier

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for SearchTier

impl Eq for SearchTier

impl StructuralPartialEq for SearchTier