Clean up the code a bit

crates/dump/src/lib.rs

@@ -305,6 +305,7 @@ pub(crate) mod test {
             localized_attributes: Setting::NotSet,
             facet_search: Setting::NotSet,
             prefix_search: Setting::NotSet,
+            chat: Setting::NotSet,
             _kind: std::marker::PhantomData,
         };
         settings.check()

crates/index-scheduler/src/insta_snapshot.rs

@@ -34,6 +34,7 @@ pub fn snapshot_index_scheduler(scheduler: &IndexScheduler) -> String {
         planned_failures: _,
         run_loop_iteration: _,
         embedders: _,
+        chat_settings: _,
     } = scheduler;
 
     let rtxn = env.read_txn().unwrap();

crates/meilisearch-auth/src/lib.rs

@@ -165,6 +165,7 @@ impl AuthController {
     }
 }
 
+#[derive(Debug)]
 pub struct AuthFilter {
     search_rules: Option<SearchRules>,
     key_authorized_indexes: SearchRules,

crates/meilisearch-types/src/deserr/mod.rs

@@ -4,9 +4,12 @@ use std::marker::PhantomData;
 use std::ops::ControlFlow;
 
 use deserr::errors::{JsonError, QueryParamError};
-use deserr::{take_cf_content, DeserializeError, IntoValue, MergeWithError, ValuePointerRef};
+use deserr::{
+    take_cf_content, DeserializeError, Deserr, IntoValue, MergeWithError, ValuePointerRef,
+};
+use milli::update::ChatSettings;
 
-use crate::error::deserr_codes::*;
+use crate::error::deserr_codes::{self, *};
 use crate::error::{
     Code, DeserrParseBoolError, DeserrParseIntError, ErrorCode, InvalidTaskDateError,
     ParseOffsetDateTimeError,
@@ -33,6 +36,7 @@ pub struct DeserrError<Format, C: Default + ErrorCode> {
     pub code: Code,
     _phantom: PhantomData<(Format, C)>,
 }
+
 impl<Format, C: Default + ErrorCode> DeserrError<Format, C> {
     pub fn new(msg: String, code: Code) -> Self {
         Self { msg, code, _phantom: PhantomData }
@@ -117,6 +121,16 @@ impl<C: Default + ErrorCode> DeserializeError for DeserrQueryParamError<C> {
     }
 }
 
+impl Deserr<DeserrError<DeserrJson, deserr_codes::InvalidSettingsIndexChat>> for ChatSettings {
+    fn deserialize_from_value<V: IntoValue>(
+        value: deserr::Value<V>,
+        location: ValuePointerRef,
+    ) -> Result<Self, DeserrError<DeserrJson, deserr_codes::InvalidSettingsIndexChat>> {
+        Deserr::<JsonError>::deserialize_from_value(value, location)
+            .map_err(|e| DeserrError::new(e.to_string(), InvalidSettingsIndexChat.error_code()))
+    }
+}
+
 pub fn immutable_field_error(field: &str, accepted: &[&str], code: Code) -> DeserrJsonError {
     let msg = format!(
         "Immutable field `{field}`: expected one of {}",

crates/meilisearch-types/src/keys.rs

@@ -326,6 +326,9 @@ pub enum Action {
     #[serde(rename = "chat.get")]
     #[deserr(rename = "chat.get")]
     Chat,
+    #[serde(rename = "chatSettings.*")]
+    #[deserr(rename = "chatSettings.*")]
+    ChatSettingsAll,
     #[serde(rename = "chatSettings.get")]
     #[deserr(rename = "chatSettings.get")]
     ChatSettingsGet,
@@ -357,6 +360,9 @@ impl Action {
             SETTINGS_ALL => Some(Self::SettingsAll),
             SETTINGS_GET => Some(Self::SettingsGet),
             SETTINGS_UPDATE => Some(Self::SettingsUpdate),
+            CHAT_SETTINGS_ALL => Some(Self::ChatSettingsAll),
+            CHAT_SETTINGS_GET => Some(Self::ChatSettingsGet),
+            CHAT_SETTINGS_UPDATE => Some(Self::ChatSettingsUpdate),
             STATS_ALL => Some(Self::StatsAll),
             STATS_GET => Some(Self::StatsGet),
             METRICS_ALL => Some(Self::MetricsAll),
@@ -424,6 +430,7 @@ pub mod actions {
     pub const NETWORK_UPDATE: u8 = NetworkUpdate.repr();
 
     pub const CHAT: u8 = Chat.repr();
+    pub const CHAT_SETTINGS_ALL: u8 = ChatSettingsAll.repr();
     pub const CHAT_SETTINGS_GET: u8 = ChatSettingsGet.repr();
     pub const CHAT_SETTINGS_UPDATE: u8 = ChatSettingsUpdate.repr();
 }

crates/meilisearch-types/src/settings.rs

@@ -186,7 +186,7 @@ impl<E: DeserializeError> Deserr<E> for SettingEmbeddingSettings {
 /// Holds all the settings for an index. `T` can either be `Checked` if they represents settings
 /// whose validity is guaranteed, or `Unchecked` if they need to be validated. In the later case, a
 /// call to `check` will return a `Settings<Checked>` from a `Settings<Unchecked>`.
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr, ToSchema)]
+#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Deserr, ToSchema)]
 #[serde(
     deny_unknown_fields,
     rename_all = "camelCase",

crates/meilisearch-types/src/task_view.rs

@@ -8,7 +8,7 @@ use crate::error::ResponseError;
 use crate::settings::{Settings, Unchecked};
 use crate::tasks::{serialize_duration, Details, IndexSwap, Kind, Status, Task, TaskId};
 
-#[derive(Debug, Clone, PartialEq, Eq, Serialize, ToSchema)]
+#[derive(Debug, Clone, PartialEq, Serialize, ToSchema)]
 #[serde(rename_all = "camelCase")]
 #[schema(rename_all = "camelCase")]
 pub struct TaskView {
@@ -67,7 +67,7 @@ impl TaskView {
     }
 }
 
-#[derive(Default, Debug, PartialEq, Eq, Clone, Serialize, Deserialize, ToSchema)]
+#[derive(Default, Debug, PartialEq, Clone, Serialize, Deserialize, ToSchema)]
 #[serde(rename_all = "camelCase")]
 #[schema(rename_all = "camelCase")]
 pub struct DetailsView {

crates/meilisearch-types/src/tasks.rs

@@ -597,7 +597,7 @@ impl fmt::Display for ParseTaskKindError {
 }
 impl std::error::Error for ParseTaskKindError {}
 
-#[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
+#[derive(Debug, PartialEq, Clone, Serialize, Deserialize)]
 pub enum Details {
     DocumentAdditionOrUpdate {
         received_documents: u64,

crates/meilisearch/src/routes/settings/chat.rs

@@ -3,6 +3,7 @@ use actix_web::HttpResponse;
 use index_scheduler::IndexScheduler;
 use meilisearch_types::error::ResponseError;
 use meilisearch_types::keys::actions;
+use meilisearch_types::milli::update::Setting;
 use serde::{Deserialize, Serialize};
 
 use crate::extractors::authentication::policies::ActionPolicy;
@@ -23,10 +24,11 @@ async fn get_settings(
         Data<IndexScheduler>,
     >,
 ) -> Result<HttpResponse, ResponseError> {
-    let settings = match index_scheduler.chat_settings()? {
+    let mut settings = match index_scheduler.chat_settings()? {
         Some(value) => serde_json::from_value(value).unwrap(),
         None => GlobalChatSettings::default(),
     };
+    settings.hide_secrets();
     Ok(HttpResponse::Ok().json(settings))
 }
 
@@ -35,37 +37,96 @@ async fn patch_settings(
         ActionPolicy<{ actions::CHAT_SETTINGS_UPDATE }>,
         Data<IndexScheduler>,
     >,
-    web::Json(chat_settings): web::Json<GlobalChatSettings>,
+    web::Json(new): web::Json<GlobalChatSettings>,
 ) -> Result<HttpResponse, ResponseError> {
-    let chat_settings = serde_json::to_value(chat_settings).unwrap();
-    index_scheduler.put_chat_settings(&chat_settings)?;
+    let old = match index_scheduler.chat_settings()? {
+        Some(value) => serde_json::from_value(value).unwrap(),
+        None => GlobalChatSettings::default(),
+    };
+
+    let settings = GlobalChatSettings {
+        source: new.source.or(old.source),
+        base_api: new.base_api.clone().or(old.base_api),
+        api_key: new.api_key.clone().or(old.api_key),
+        prompts: match (new.prompts, old.prompts) {
+            (Setting::NotSet, set) | (set, Setting::NotSet) => set,
+            (Setting::Set(_) | Setting::Reset, Setting::Reset) => Setting::Reset,
+            (Setting::Reset, Setting::Set(set)) => Setting::Set(set),
+            // If both are set we must merge the prompts settings
+            (Setting::Set(new), Setting::Set(old)) => Setting::Set(ChatPrompts {
+                system: new.system.or(old.system),
+                search_description: new.search_description.or(old.search_description),
+                search_q_param: new.search_q_param.or(old.search_q_param),
+                search_index_uid_param: new.search_index_uid_param.or(old.search_index_uid_param),
+                pre_query: new.pre_query.or(old.pre_query),
+            }),
+        },
+    };
+
+    let value = serde_json::to_value(settings).unwrap();
+    index_scheduler.put_chat_settings(&value)?;
     Ok(HttpResponse::Ok().finish())
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields, rename_all = "camelCase")]
+pub enum ChatSource {
+    OpenAi,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
 pub struct GlobalChatSettings {
-    pub source: String,
-    pub base_api: Option<String>,
-    pub api_key: Option<String>,
-    pub prompts: ChatPrompts,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub source: Setting<ChatSource>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub base_api: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub api_key: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub prompts: Setting<ChatPrompts>,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+impl GlobalChatSettings {
+    pub fn hide_secrets(&mut self) {
+        match &mut self.api_key {
+            Setting::Set(key) => Self::hide_secret(key),
+            Setting::Reset => (),
+            Setting::NotSet => (),
+        }
+    }
+
+    fn hide_secret(secret: &mut String) {
+        match secret.len() {
+            x if x < 10 => {
+                secret.replace_range(.., "XXX...");
+            }
+            x if x < 20 => {
+                secret.replace_range(2.., "XXXX...");
+            }
+            x if x < 30 => {
+                secret.replace_range(3.., "XXXXX...");
+            }
+            _x => {
+                secret.replace_range(5.., "XXXXXX...");
+            }
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
 pub struct ChatPrompts {
-    pub system: String,
-    pub search_description: String,
-    pub search_q_param: String,
-    pub search_index_uid_param: String,
-    pub pre_query: String,
-}
-
-#[derive(Debug, Serialize, Deserialize)]
-#[serde(deny_unknown_fields, rename_all = "camelCase")]
-pub struct ChatIndexSettings {
-    pub description: String,
-    pub document_template: String,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub system: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub search_description: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub search_q_param: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub search_index_uid_param: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    pub pre_query: Setting<String>,
 }
 
 const DEFAULT_SYSTEM_MESSAGE: &str = "You are a highly capable research assistant with access to powerful search tools. IMPORTANT INSTRUCTIONS:\
@@ -91,17 +152,26 @@ Selecting the right index ensures the most relevant results for the user query";
 impl Default for GlobalChatSettings {
     fn default() -> Self {
         GlobalChatSettings {
-            source: "openai".to_string(),
-            base_api: None,
-            api_key: None,
-            prompts: ChatPrompts {
-                system: DEFAULT_SYSTEM_MESSAGE.to_string(),
-                search_description: DEFAULT_SEARCH_IN_INDEX_TOOL_DESCRIPTION.to_string(),
-                search_q_param: DEFAULT_SEARCH_IN_INDEX_Q_PARAMETER_TOOL_DESCRIPTION.to_string(),
-                search_index_uid_param: DEFAULT_SEARCH_IN_INDEX_INDEX_PARAMETER_TOOL_DESCRIPTION
-                    .to_string(),
-                pre_query: "".to_string(),
-            },
+            source: Setting::NotSet,
+            base_api: Setting::NotSet,
+            api_key: Setting::NotSet,
+            prompts: Setting::Set(ChatPrompts::default()),
+        }
+    }
+}
+
+impl Default for ChatPrompts {
+    fn default() -> Self {
+        ChatPrompts {
+            system: Setting::Set(DEFAULT_SYSTEM_MESSAGE.to_string()),
+            search_description: Setting::Set(DEFAULT_SEARCH_IN_INDEX_TOOL_DESCRIPTION.to_string()),
+            search_q_param: Setting::Set(
+                DEFAULT_SEARCH_IN_INDEX_Q_PARAMETER_TOOL_DESCRIPTION.to_string(),
+            ),
+            search_index_uid_param: Setting::Set(
+                DEFAULT_SEARCH_IN_INDEX_INDEX_PARAMETER_TOOL_DESCRIPTION.to_string(),
+            ),
+            pre_query: Setting::Set(Default::default()),
         }
     }
 }

crates/meilisearch/src/search/mod.rs

@@ -122,6 +122,7 @@ pub struct SearchQuery {
 #[derive(Debug, Clone, Copy, PartialEq, Deserr, ToSchema, Serialize)]
 #[deserr(try_from(f64) = TryFrom::try_from -> InvalidSearchRankingScoreThreshold)]
 pub struct RankingScoreThreshold(f64);
+
 impl std::convert::TryFrom<f64> for RankingScoreThreshold {
     type Error = InvalidSearchRankingScoreThreshold;
 
@@ -279,8 +280,8 @@ impl fmt::Debug for SearchQuery {
 #[deserr(error = DeserrJsonError<InvalidSearchHybridQuery>, rename_all = camelCase, deny_unknown_fields)]
 #[serde(rename_all = "camelCase")]
 pub struct HybridQuery {
-    #[deserr(default, error = DeserrJsonError<InvalidSearchSemanticRatio>, default)]
-    #[schema(value_type = f32, default)]
+    #[deserr(default, error = DeserrJsonError<InvalidSearchSemanticRatio>)]
+    #[schema(default, value_type = f32)]
     #[serde(default)]
     pub semantic_ratio: SemanticRatio,
     #[deserr(error = DeserrJsonError<InvalidSearchEmbedder>)]

crates/milli/src/index.rs

@@ -1695,7 +1695,7 @@ impl Index {
 
     pub fn chat_config(&self, txn: &RoTxn<'_>) -> heed::Result<ChatConfig> {
         self.main
-            .remap_types::<Str, SerdeBincode<_>>()
+            .remap_types::<Str, SerdeJson<_>>()
             .get(txn, main_key::CHAT)
             .map(|o| o.unwrap_or_default())
     }
@@ -1705,7 +1705,7 @@ impl Index {
         txn: &mut RwTxn<'_>,
         val: &ChatConfig,
     ) -> heed::Result<()> {
-        self.main.remap_types::<Str, SerdeBincode<_>>().put(txn, main_key::CHAT, &val)
+        self.main.remap_types::<Str, SerdeJson<_>>().put(txn, main_key::CHAT, &val)
     }
 
     pub(crate) fn delete_chat_config(&self, txn: &mut RwTxn<'_>) -> heed::Result<bool> {
@@ -1943,15 +1943,54 @@ pub struct ChatConfig {
     pub description: String,
     /// Contains the document template and max template length.
     pub prompt: PromptData,
+    pub search_parameters: SearchParameters,
+}
+
+#[derive(Debug, Default, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SearchParameters {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub hybrid: Option<HybridQuery>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub limit: Option<usize>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub sort: Option<Vec<String>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub distinct: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub matching_strategy: Option<MatchingStrategy>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub attributes_to_search_on: Option<Vec<String>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub ranking_score_threshold: Option<f64>,
+}
+
+#[derive(Debug, Default, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct HybridQuery {
+    pub semantic_ratio: f32,
+    pub embedder: String,
 }
 
 #[derive(Debug, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct PrefixSettings {
     pub prefix_count_threshold: usize,
     pub max_prefix_length: usize,
     pub compute_prefixes: PrefixSearch,
 }
 
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum MatchingStrategy {
+    /// Remove query words from last to first
+    Last,
+    /// All query words are mandatory
+    All,
+    /// Remove query words from the most frequent to the least
+    Frequency,
+}
+
 #[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq, Default)]
 #[serde(rename_all = "camelCase")]
 pub enum PrefixSearch {

crates/milli/src/prompt/mod.rs

@@ -105,10 +105,10 @@ impl Prompt {
             max_bytes,
         };
 
-        // render template with special object that's OK with `doc.*` and `fields.*`
-        this.template
-            .render(&template_checker::TemplateChecker)
-            .map_err(NewPromptError::invalid_fields_in_template)?;
+        // // render template with special object that's OK with `doc.*` and `fields.*`
+        // this.template
+        //     .render(&template_checker::TemplateChecker)
+        //     .map_err(NewPromptError::invalid_fields_in_template)?;
 
         Ok(this)
     }

crates/milli/src/update/chat.rs

@@ -1,14 +1,19 @@
+use std::error::Error;
+use std::fmt;
+
+use deserr::errors::JsonError;
 use deserr::Deserr;
 use serde::{Deserialize, Serialize};
 use utoipa::ToSchema;
 
-use crate::index::ChatConfig;
+use crate::index::{self, ChatConfig, SearchParameters};
 use crate::prompt::{default_max_bytes, PromptData};
 use crate::update::Setting;
+use crate::TermsMatchingStrategy;
 
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr, ToSchema)]
+#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Deserr, ToSchema)]
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
-#[deserr(deny_unknown_fields, rename_all = camelCase)]
+#[deserr(error = JsonError, deny_unknown_fields, rename_all = camelCase)]
 pub struct ChatSettings {
     #[serde(default, skip_serializing_if = "Setting::is_not_set")]
     #[deserr(default)]
@@ -29,17 +34,226 @@ pub struct ChatSettings {
     #[deserr(default)]
     #[schema(value_type = Option<usize>)]
     pub document_template_max_bytes: Setting<usize>,
+
+    /// The search parameters to use for the LLM.
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<ChatSearchParams>)]
+    pub search_parameters: Setting<ChatSearchParams>,
 }
 
 impl From<ChatConfig> for ChatSettings {
     fn from(config: ChatConfig) -> Self {
-        let ChatConfig { description, prompt: PromptData { template, max_bytes } } = config;
+        let ChatConfig {
+            description,
+            prompt: PromptData { template, max_bytes },
+            search_parameters,
+        } = config;
         ChatSettings {
             description: Setting::Set(description),
             document_template: Setting::Set(template),
             document_template_max_bytes: Setting::Set(
                 max_bytes.unwrap_or(default_max_bytes()).get(),
             ),
+            search_parameters: Setting::Set({
+                let SearchParameters {
+                    hybrid,
+                    limit,
+                    sort,
+                    distinct,
+                    matching_strategy,
+                    attributes_to_search_on,
+                    ranking_score_threshold,
+                } = search_parameters;
+
+                let hybrid = hybrid.map(|index::HybridQuery { semantic_ratio, embedder }| {
+                    HybridQuery { semantic_ratio: SemanticRatio(semantic_ratio), embedder }
+                });
+
+                let matching_strategy = matching_strategy.map(|ms| match ms {
+                    index::MatchingStrategy::Last => MatchingStrategy::Last,
+                    index::MatchingStrategy::All => MatchingStrategy::All,
+                    index::MatchingStrategy::Frequency => MatchingStrategy::Frequency,
+                });
+
+                let ranking_score_threshold = ranking_score_threshold.map(RankingScoreThreshold);
+
+                ChatSearchParams {
+                    hybrid: Setting::some_or_not_set(hybrid),
+                    limit: Setting::some_or_not_set(limit),
+                    sort: Setting::some_or_not_set(sort),
+                    distinct: Setting::some_or_not_set(distinct),
+                    matching_strategy: Setting::some_or_not_set(matching_strategy),
+                    attributes_to_search_on: Setting::some_or_not_set(attributes_to_search_on),
+                    ranking_score_threshold: Setting::some_or_not_set(ranking_score_threshold),
+                }
+            }),
         }
     }
 }
+
+#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Deserr, ToSchema)]
+#[serde(deny_unknown_fields, rename_all = "camelCase")]
+#[deserr(error = JsonError, deny_unknown_fields, rename_all = camelCase)]
+pub struct ChatSearchParams {
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<HybridQuery>)]
+    pub hybrid: Setting<HybridQuery>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default = Setting::Set(20))]
+    #[schema(value_type = Option<usize>)]
+    pub limit: Setting<usize>,
+
+    // #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    // #[deserr(default)]
+    // pub attributes_to_retrieve: Option<BTreeSet<String>>,
+
+    // #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    // #[deserr(default)]
+    // pub filter: Option<Value>,
+    //
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<Vec<String>>)]
+    pub sort: Setting<Vec<String>>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<String>)]
+    pub distinct: Setting<String>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<MatchingStrategy>)]
+    pub matching_strategy: Setting<MatchingStrategy>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<Vec<String>>)]
+    pub attributes_to_search_on: Setting<Vec<String>>,
+
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    #[schema(value_type = Option<RankingScoreThreshold>)]
+    pub ranking_score_threshold: Setting<RankingScoreThreshold>,
+}
+
+#[derive(Debug, Clone, Default, Deserr, ToSchema, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[deserr(error = JsonError, rename_all = camelCase, deny_unknown_fields)]
+pub struct HybridQuery {
+    #[deserr(default)]
+    #[serde(default)]
+    #[schema(default, value_type = f32)]
+    pub semantic_ratio: SemanticRatio,
+    #[schema(value_type = String)]
+    pub embedder: String,
+}
+
+#[derive(Debug, Clone, Copy, Deserr, ToSchema, PartialEq, Serialize, Deserialize)]
+#[deserr(try_from(f32) = TryFrom::try_from -> InvalidSearchSemanticRatio)]
+pub struct SemanticRatio(f32);
+
+impl Default for SemanticRatio {
+    fn default() -> Self {
+        SemanticRatio(0.5)
+    }
+}
+
+impl std::convert::TryFrom<f32> for SemanticRatio {
+    type Error = InvalidSearchSemanticRatio;
+
+    fn try_from(f: f32) -> Result<Self, Self::Error> {
+        // the suggested "fix" is: `!(0.0..=1.0).contains(&f)`` which is allegedly less readable
+        #[allow(clippy::manual_range_contains)]
+        if f > 1.0 || f < 0.0 {
+            Err(InvalidSearchSemanticRatio)
+        } else {
+            Ok(SemanticRatio(f))
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct InvalidSearchSemanticRatio;
+
+impl Error for InvalidSearchSemanticRatio {}
+
+impl fmt::Display for InvalidSearchSemanticRatio {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "the value of `semanticRatio` is invalid, expected a float between `0.0` and `1.0`."
+        )
+    }
+}
+
+impl std::ops::Deref for SemanticRatio {
+    type Target = f32;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Deserr, ToSchema, Serialize, Deserialize)]
+#[deserr(rename_all = camelCase)]
+#[serde(rename_all = "camelCase")]
+pub enum MatchingStrategy {
+    /// Remove query words from last to first
+    Last,
+    /// All query words are mandatory
+    All,
+    /// Remove query words from the most frequent to the least
+    Frequency,
+}
+
+impl Default for MatchingStrategy {
+    fn default() -> Self {
+        Self::Last
+    }
+}
+
+impl From<MatchingStrategy> for TermsMatchingStrategy {
+    fn from(other: MatchingStrategy) -> Self {
+        match other {
+            MatchingStrategy::Last => Self::Last,
+            MatchingStrategy::All => Self::All,
+            MatchingStrategy::Frequency => Self::Frequency,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Deserr, ToSchema, Serialize, Deserialize)]
+#[deserr(try_from(f64) = TryFrom::try_from -> InvalidSearchRankingScoreThreshold)]
+pub struct RankingScoreThreshold(pub f64);
+
+impl std::convert::TryFrom<f64> for RankingScoreThreshold {
+    type Error = InvalidSearchRankingScoreThreshold;
+
+    fn try_from(f: f64) -> Result<Self, Self::Error> {
+        // the suggested "fix" is: `!(0.0..=1.0).contains(&f)`` which is allegedly less readable
+        #[allow(clippy::manual_range_contains)]
+        if f > 1.0 || f < 0.0 {
+            Err(InvalidSearchRankingScoreThreshold)
+        } else {
+            Ok(RankingScoreThreshold(f))
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct InvalidSearchRankingScoreThreshold;
+
+impl Error for InvalidSearchRankingScoreThreshold {}
+
+impl fmt::Display for InvalidSearchRankingScoreThreshold {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "the value of `rankingScoreThreshold` is invalid, expected a float between `0.0` and `1.0`."
+        )
+    }
+}

crates/milli/src/update/settings.rs

@@ -11,6 +11,7 @@ use roaring::RoaringBitmap;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use time::OffsetDateTime;
 
+use super::chat::{ChatSearchParams, RankingScoreThreshold};
 use super::del_add::{DelAdd, DelAddOperation};
 use super::index_documents::{IndexDocumentsConfig, Transform};
 use super::{ChatSettings, IndexerConfig};
@@ -22,8 +23,8 @@ use crate::error::UserError;
 use crate::fields_ids_map::metadata::{FieldIdMapWithMetadata, MetadataBuilder};
 use crate::filterable_attributes_rules::match_faceted_field;
 use crate::index::{
-    ChatConfig, IndexEmbeddingConfig, PrefixSearch, DEFAULT_MIN_WORD_LEN_ONE_TYPO,
-    DEFAULT_MIN_WORD_LEN_TWO_TYPOS,
+    ChatConfig, IndexEmbeddingConfig, MatchingStrategy, PrefixSearch,
+    DEFAULT_MIN_WORD_LEN_ONE_TYPO, DEFAULT_MIN_WORD_LEN_TWO_TYPOS,
 };
 use crate::order_by_map::OrderByMap;
 use crate::prompt::{default_max_bytes, PromptData};
@@ -123,6 +124,15 @@ impl<T> Setting<T> {
         *self = new;
         true
     }
+
+    #[track_caller]
+    pub fn unwrap(self) -> T {
+        match self {
+            Setting::Set(value) => value,
+            Setting::Reset => panic!("Setting::Reset unwrapped"),
+            Setting::NotSet => panic!("Setting::NotSet unwrapped"),
+        }
+    }
 }
 
 impl<T: Serialize> Serialize for Setting<T> {
@@ -1255,11 +1265,13 @@ impl<'a, 't, 'i> Settings<'a, 't, 'i> {
                 description: new_description,
                 document_template: new_document_template,
                 document_template_max_bytes: new_document_template_max_bytes,
+                search_parameters: new_search_parameters,
             }) => {
                 let mut old = self.index.chat_config(self.wtxn)?;
                 let ChatConfig {
                     ref mut description,
                     prompt: PromptData { ref mut template, ref mut max_bytes },
+                    ref mut search_parameters,
                 } = old;
 
                 match new_description {
@@ -1280,6 +1292,85 @@ impl<'a, 't, 'i> Settings<'a, 't, 'i> {
                     Setting::NotSet => (),
                 }
 
+                match new_search_parameters {
+                    Setting::Set(sp) => {
+                        let ChatSearchParams {
+                            hybrid,
+                            limit,
+                            sort,
+                            distinct,
+                            matching_strategy,
+                            attributes_to_search_on,
+                            ranking_score_threshold,
+                        } = sp;
+
+                        match hybrid {
+                            Setting::Set(hybrid) => {
+                                search_parameters.hybrid = Some(crate::index::HybridQuery {
+                                    semantic_ratio: *hybrid.semantic_ratio,
+                                    embedder: hybrid.embedder.clone(),
+                                })
+                            }
+                            Setting::Reset => search_parameters.hybrid = None,
+                            Setting::NotSet => (),
+                        }
+
+                        match limit {
+                            Setting::Set(limit) => search_parameters.limit = Some(*limit),
+                            Setting::Reset => search_parameters.limit = None,
+                            Setting::NotSet => (),
+                        }
+
+                        match sort {
+                            Setting::Set(sort) => search_parameters.sort = Some(sort.clone()),
+                            Setting::Reset => search_parameters.sort = None,
+                            Setting::NotSet => (),
+                        }
+
+                        match distinct {
+                            Setting::Set(distinct) => {
+                                search_parameters.distinct = Some(distinct.clone())
+                            }
+                            Setting::Reset => search_parameters.distinct = None,
+                            Setting::NotSet => (),
+                        }
+
+                        match matching_strategy {
+                            Setting::Set(matching_strategy) => {
+                                let strategy = match matching_strategy {
+                                    super::chat::MatchingStrategy::Last => MatchingStrategy::Last,
+                                    super::chat::MatchingStrategy::All => MatchingStrategy::All,
+                                    super::chat::MatchingStrategy::Frequency => {
+                                        MatchingStrategy::Frequency
+                                    }
+                                };
+                                search_parameters.matching_strategy = Some(strategy)
+                            }
+                            Setting::Reset => search_parameters.matching_strategy = None,
+                            Setting::NotSet => (),
+                        }
+
+                        match attributes_to_search_on {
+                            Setting::Set(attributes_to_search_on) => {
+                                search_parameters.attributes_to_search_on =
+                                    Some(attributes_to_search_on.clone())
+                            }
+                            Setting::Reset => search_parameters.attributes_to_search_on = None,
+                            Setting::NotSet => (),
+                        }
+
+                        match ranking_score_threshold {
+                            Setting::Set(RankingScoreThreshold(score)) => {
+                                search_parameters.ranking_score_threshold = Some(*score)
+                            }
+                            Setting::Reset => search_parameters.ranking_score_threshold = None,
+                            Setting::NotSet => (),
+                        }
+                    }
+                    Setting::Reset => *search_parameters = Default::default(),
+                    Setting::NotSet => (),
+                }
+
                 self.index.put_chat_config(self.wtxn, &old)?;
                 Ok(true)
             }

crates/milli/src/update/test_settings.rs

@@ -897,6 +897,7 @@ fn test_correct_settings_init() {
                 prefix_search,
                 facet_search,
                 disable_on_numbers,
+                chat,
             } = settings;
             assert!(matches!(searchable_fields, Setting::NotSet));
             assert!(matches!(displayed_fields, Setting::NotSet));