diff --git a/milli/src/vector/openai.rs b/milli/src/vector/openai.rs
index c11e6ddc6..53e8a041b 100644
--- a/milli/src/vector/openai.rs
+++ b/milli/src/vector/openai.rs
@@ -34,6 +34,9 @@ pub struct EmbedderOptions {
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
 #[deserr(rename_all = camelCase, deny_unknown_fields)]
 pub enum EmbeddingModel {
+    // # WARNING
+    //
+    // If ever adding a model, make sure to add it to the list of supported models below.
     #[default]
     #[serde(rename = "text-embedding-ada-002")]
     #[deserr(rename = "text-embedding-ada-002")]
@@ -41,6 +44,10 @@ pub enum EmbeddingModel {
 }
 
 impl EmbeddingModel {
+    pub fn supported_models() -> &'static [&'static str] {
+        &["text-embedding-ada-002"]
+    }
+
     pub fn max_token(&self) -> usize {
         match self {
             EmbeddingModel::TextEmbeddingAda002 => 8191,
@@ -59,7 +66,7 @@ impl EmbeddingModel {
         }
     }
 
-    pub fn from_name(name: &'static str) -> Option<Self> {
+    pub fn from_name(name: &str) -> Option<Self> {
         match name {
             "text-embedding-ada-002" => Some(EmbeddingModel::TextEmbeddingAda002),
             _ => None,
diff --git a/milli/src/vector/settings.rs b/milli/src/vector/settings.rs
index 1826c040d..945fc62c0 100644
--- a/milli/src/vector/settings.rs
+++ b/milli/src/vector/settings.rs
@@ -4,32 +4,189 @@ use serde::{Deserialize, Serialize};
 use crate::prompt::PromptData;
 use crate::update::Setting;
 use crate::vector::EmbeddingConfig;
+use crate::UserError;
 
 #[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr)]
 #[serde(deny_unknown_fields, rename_all = "camelCase")]
 #[deserr(rename_all = camelCase, deny_unknown_fields)]
 pub struct EmbeddingSettings {
-    #[serde(default, skip_serializing_if = "Setting::is_not_set", rename = "source")]
-    #[deserr(default, rename = "source")]
-    pub embedder_options: Setting<EmbedderSettings>,
     #[serde(default, skip_serializing_if = "Setting::is_not_set")]
     #[deserr(default)]
-    pub document_template: Setting<PromptSettings>,
+    pub source: Setting<EmbedderSource>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    pub model: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    pub revision: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    pub api_key: Setting<String>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    pub dimensions: Setting<usize>,
+    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
+    #[deserr(default)]
+    pub document_template: Setting<String>,
+}
+
+pub fn check_unset<T>(
+    key: &Setting<T>,
+    field: &'static str,
+    source: EmbedderSource,
+    embedder_name: &str,
+) -> Result<(), UserError> {
+    if matches!(key, Setting::NotSet) {
+        Ok(())
+    } else {
+        Err(UserError::InvalidFieldForSource {
+            embedder_name: embedder_name.to_owned(),
+            source_: source,
+            field,
+            allowed_fields_for_source: EmbeddingSettings::allowed_fields_for_source(source),
+            allowed_sources_for_field: EmbeddingSettings::allowed_sources_for_field(field),
+        })
+    }
+}
+
+pub fn check_set<T>(
+    key: &Setting<T>,
+    field: &'static str,
+    source: EmbedderSource,
+    embedder_name: &str,
+) -> Result<(), UserError> {
+    if matches!(key, Setting::Set(_)) {
+        Ok(())
+    } else {
+        Err(UserError::MissingFieldForSource {
+            field,
+            source_: source,
+            embedder_name: embedder_name.to_owned(),
+        })
+    }
+}
+
+impl EmbeddingSettings {
+    pub const SOURCE: &str = "source";
+    pub const MODEL: &str = "model";
+    pub const REVISION: &str = "revision";
+    pub const API_KEY: &str = "apiKey";
+    pub const DIMENSIONS: &str = "dimensions";
+    pub const DOCUMENT_TEMPLATE: &str = "documentTemplate";
+
+    pub fn allowed_sources_for_field(field: &'static str) -> &'static [EmbedderSource] {
+        match field {
+            Self::SOURCE => {
+                &[EmbedderSource::HuggingFace, EmbedderSource::OpenAi, EmbedderSource::UserProvided]
+            }
+            Self::MODEL => &[EmbedderSource::HuggingFace, EmbedderSource::OpenAi],
+            Self::REVISION => &[EmbedderSource::HuggingFace],
+            Self::API_KEY => &[EmbedderSource::OpenAi],
+            Self::DIMENSIONS => &[EmbedderSource::UserProvided],
+            Self::DOCUMENT_TEMPLATE => &[EmbedderSource::HuggingFace, EmbedderSource::OpenAi],
+            _other => unreachable!("unknown field"),
+        }
+    }
+
+    pub fn allowed_fields_for_source(source: EmbedderSource) -> &'static [&'static str] {
+        match source {
+            EmbedderSource::OpenAi => {
+                &[Self::SOURCE, Self::MODEL, Self::API_KEY, Self::DOCUMENT_TEMPLATE]
+            }
+            EmbedderSource::HuggingFace => {
+                &[Self::SOURCE, Self::MODEL, Self::REVISION, Self::DOCUMENT_TEMPLATE]
+            }
+            EmbedderSource::UserProvided => &[Self::SOURCE, Self::DIMENSIONS],
+        }
+    }
+
+    pub(crate) fn apply_default_source(setting: &mut Setting<EmbeddingSettings>) {
+        if let Setting::Set(EmbeddingSettings {
+            source: source @ (Setting::NotSet | Setting::Reset),
+            ..
+        }) = setting
+        {
+            *source = Setting::Set(EmbedderSource::default())
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, Default, Serialize, Deserialize, PartialEq, Eq, Deserr)]
+#[serde(deny_unknown_fields, rename_all = "camelCase")]
+#[deserr(rename_all = camelCase, deny_unknown_fields)]
+pub enum EmbedderSource {
+    #[default]
+    OpenAi,
+    HuggingFace,
+    UserProvided,
+}
+
+impl std::fmt::Display for EmbedderSource {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let s = match self {
+            EmbedderSource::OpenAi => "openAi",
+            EmbedderSource::HuggingFace => "huggingFace",
+            EmbedderSource::UserProvided => "userProvided",
+        };
+        f.write_str(s)
+    }
 }
 
 impl EmbeddingSettings {
     pub fn apply(&mut self, new: Self) {
-        let EmbeddingSettings { embedder_options, document_template: prompt } = new;
-        self.embedder_options.apply(embedder_options);
-        self.document_template.apply(prompt);
+        let EmbeddingSettings { source, model, revision, api_key, dimensions, document_template } =
+            new;
+        let old_source = self.source;
+        self.source.apply(source);
+        // Reinitialize the whole setting object on a source change
+        if old_source != self.source {
+            *self = EmbeddingSettings {
+                source,
+                model,
+                revision,
+                api_key,
+                dimensions,
+                document_template,
+            };
+            return;
+        }
+
+        self.model.apply(model);
+        self.revision.apply(revision);
+        self.api_key.apply(api_key);
+        self.dimensions.apply(dimensions);
+        self.document_template.apply(document_template);
     }
 }
 
 impl From<EmbeddingConfig> for EmbeddingSettings {
     fn from(value: EmbeddingConfig) -> Self {
-        Self {
-            embedder_options: Setting::Set(value.embedder_options.into()),
-            document_template: Setting::Set(value.prompt.into()),
+        let EmbeddingConfig { embedder_options, prompt } = value;
+        match embedder_options {
+            super::EmbedderOptions::HuggingFace(options) => Self {
+                source: Setting::Set(EmbedderSource::HuggingFace),
+                model: Setting::Set(options.model),
+                revision: options.revision.map(Setting::Set).unwrap_or_default(),
+                api_key: Setting::NotSet,
+                dimensions: Setting::NotSet,
+                document_template: Setting::Set(prompt.template),
+            },
+            super::EmbedderOptions::OpenAi(options) => Self {
+                source: Setting::Set(EmbedderSource::OpenAi),
+                model: Setting::Set(options.embedding_model.name().to_owned()),
+                revision: Setting::NotSet,
+                api_key: options.api_key.map(Setting::Set).unwrap_or_default(),
+                dimensions: Setting::NotSet,
+                document_template: Setting::Set(prompt.template),
+            },
+            super::EmbedderOptions::UserProvided(options) => Self {
+                source: Setting::Set(EmbedderSource::UserProvided),
+                model: Setting::NotSet,
+                revision: Setting::NotSet,
+                api_key: Setting::NotSet,
+                dimensions: Setting::Set(options.dimensions),
+                document_template: Setting::NotSet,
+            },
         }
     }
 }
@@ -37,262 +194,51 @@ impl From<EmbeddingConfig> for EmbeddingSettings {
 impl From<EmbeddingSettings> for EmbeddingConfig {
     fn from(value: EmbeddingSettings) -> Self {
         let mut this = Self::default();
-        let EmbeddingSettings { embedder_options, document_template: prompt } = value;
-        if let Some(embedder_options) = embedder_options.set() {
-            this.embedder_options = embedder_options.into();
-        }
-        if let Some(prompt) = prompt.set() {
-            this.prompt = prompt.into();
-        }
-        this
-    }
-}
-
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr)]
-#[serde(deny_unknown_fields, rename_all = "camelCase")]
-#[deserr(rename_all = camelCase, deny_unknown_fields)]
-pub struct PromptSettings {
-    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
-    #[deserr(default)]
-    pub template: Setting<String>,
-}
-
-impl PromptSettings {
-    pub fn apply(&mut self, new: Self) {
-        let PromptSettings { template } = new;
-        self.template.apply(template);
-    }
-}
-
-impl From<PromptData> for PromptSettings {
-    fn from(value: PromptData) -> Self {
-        Self { template: Setting::Set(value.template) }
-    }
-}
-
-impl From<PromptSettings> for PromptData {
-    fn from(value: PromptSettings) -> Self {
-        let mut this = PromptData::default();
-        let PromptSettings { template } = value;
-        if let Some(template) = template.set() {
-            this.template = template;
-        }
-        this
-    }
-}
-
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
-#[serde(deny_unknown_fields, rename_all = "camelCase")]
-pub enum EmbedderSettings {
-    HuggingFace(Setting<HfEmbedderSettings>),
-    OpenAi(Setting<OpenAiEmbedderSettings>),
-    UserProvided(UserProvidedSettings),
-}
-
-impl<E> Deserr<E> for EmbedderSettings
-where
-    E: deserr::DeserializeError,
-{
-    fn deserialize_from_value<V: deserr::IntoValue>(
-        value: deserr::Value<V>,
-        location: deserr::ValuePointerRef,
-    ) -> Result<Self, E> {
-        match value {
-            deserr::Value::Map(map) => {
-                if deserr::Map::len(&map) != 1 {
-                    return Err(deserr::take_cf_content(E::error::<V>(
-                        None,
-                        deserr::ErrorKind::Unexpected {
-                            msg: format!(
-                                "Expected a single field, got {} fields",
-                                deserr::Map::len(&map)
-                            ),
-                        },
-                        location,
-                    )));
+        let EmbeddingSettings { source, model, revision, api_key, dimensions, document_template } =
+            value;
+        if let Some(source) = source.set() {
+            match source {
+                EmbedderSource::OpenAi => {
+                    let mut options = super::openai::EmbedderOptions::with_default_model(None);
+                    if let Some(model) = model.set() {
+                        if let Some(model) = super::openai::EmbeddingModel::from_name(&model) {
+                            options.embedding_model = model;
+                        }
+                    }
+                    if let Some(api_key) = api_key.set() {
+                        options.api_key = Some(api_key);
+                    }
+                    this.embedder_options = super::EmbedderOptions::OpenAi(options);
                 }
-                let mut it = deserr::Map::into_iter(map);
-                let (k, v) = it.next().unwrap();
-
-                match k.as_str() {
-                    "huggingFace" => Ok(EmbedderSettings::HuggingFace(Setting::Set(
-                        HfEmbedderSettings::deserialize_from_value(
-                            v.into_value(),
-                            location.push_key(&k),
-                        )?,
-                    ))),
-                    "openAi" => Ok(EmbedderSettings::OpenAi(Setting::Set(
-                        OpenAiEmbedderSettings::deserialize_from_value(
-                            v.into_value(),
-                            location.push_key(&k),
-                        )?,
-                    ))),
-                    "userProvided" => Ok(EmbedderSettings::UserProvided(
-                        UserProvidedSettings::deserialize_from_value(
-                            v.into_value(),
-                            location.push_key(&k),
-                        )?,
-                    )),
-                    other => Err(deserr::take_cf_content(E::error::<V>(
-                        None,
-                        deserr::ErrorKind::UnknownKey {
-                            key: other,
-                            accepted: &["huggingFace", "openAi", "userProvided"],
-                        },
-                        location,
-                    ))),
+                EmbedderSource::HuggingFace => {
+                    let mut options = super::hf::EmbedderOptions::default();
+                    if let Some(model) = model.set() {
+                        options.model = model;
+                        // Reset the revision if we are setting the model.
+                        // This allows the following:
+                        // "huggingFace": {} -> default model with default revision
+                        // "huggingFace": { "model": "name-of-the-default-model" } -> default model without a revision
+                        // "huggingFace": { "model": "some-other-model" } -> most importantly, other model without a revision
+                        options.revision = None;
+                    }
+                    if let Some(revision) = revision.set() {
+                        options.revision = Some(revision);
+                    }
+                    this.embedder_options = super::EmbedderOptions::HuggingFace(options);
+                }
+                EmbedderSource::UserProvided => {
+                    this.embedder_options =
+                        super::EmbedderOptions::UserProvided(super::manual::EmbedderOptions {
+                            dimensions: dimensions.set().unwrap(),
+                        });
                 }
             }
-            _ => Err(deserr::take_cf_content(E::error::<V>(
-                None,
-                deserr::ErrorKind::IncorrectValueKind {
-                    actual: value,
-                    accepted: &[deserr::ValueKind::Map],
-                },
-                location,
-            ))),
         }
-    }
-}
 
-impl Default for EmbedderSettings {
-    fn default() -> Self {
-        Self::OpenAi(Default::default())
-    }
-}
-
-impl From<crate::vector::EmbedderOptions> for EmbedderSettings {
-    fn from(value: crate::vector::EmbedderOptions) -> Self {
-        match value {
-            crate::vector::EmbedderOptions::HuggingFace(hf) => {
-                Self::HuggingFace(Setting::Set(hf.into()))
-            }
-            crate::vector::EmbedderOptions::OpenAi(openai) => {
-                Self::OpenAi(Setting::Set(openai.into()))
-            }
-            crate::vector::EmbedderOptions::UserProvided(user_provided) => {
-                Self::UserProvided(user_provided.into())
-            }
+        if let Setting::Set(template) = document_template {
+            this.prompt = PromptData { template }
         }
-    }
-}
 
-impl From<EmbedderSettings> for crate::vector::EmbedderOptions {
-    fn from(value: EmbedderSettings) -> Self {
-        match value {
-            EmbedderSettings::HuggingFace(Setting::Set(hf)) => Self::HuggingFace(hf.into()),
-            EmbedderSettings::HuggingFace(_setting) => Self::HuggingFace(Default::default()),
-            EmbedderSettings::OpenAi(Setting::Set(ai)) => Self::OpenAi(ai.into()),
-            EmbedderSettings::OpenAi(_setting) => {
-                Self::OpenAi(crate::vector::openai::EmbedderOptions::with_default_model(None))
-            }
-            EmbedderSettings::UserProvided(user_provided) => {
-                Self::UserProvided(user_provided.into())
-            }
-        }
-    }
-}
-
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr)]
-#[serde(deny_unknown_fields, rename_all = "camelCase")]
-#[deserr(rename_all = camelCase, deny_unknown_fields)]
-pub struct HfEmbedderSettings {
-    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
-    #[deserr(default)]
-    pub model: Setting<String>,
-    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
-    #[deserr(default)]
-    pub revision: Setting<String>,
-}
-
-impl HfEmbedderSettings {
-    pub fn apply(&mut self, new: Self) {
-        let HfEmbedderSettings { model, revision } = new;
-        self.model.apply(model);
-        self.revision.apply(revision);
-    }
-}
-
-impl From<crate::vector::hf::EmbedderOptions> for HfEmbedderSettings {
-    fn from(value: crate::vector::hf::EmbedderOptions) -> Self {
-        Self {
-            model: Setting::Set(value.model),
-            revision: value.revision.map(Setting::Set).unwrap_or(Setting::NotSet),
-        }
-    }
-}
-
-impl From<HfEmbedderSettings> for crate::vector::hf::EmbedderOptions {
-    fn from(value: HfEmbedderSettings) -> Self {
-        let HfEmbedderSettings { model, revision } = value;
-        let mut this = Self::default();
-        if let Some(model) = model.set() {
-            this.model = model;
-            // Reset the revision if we are setting the model.
-            // This allows the following:
-            // "huggingFace": {} -> default model with default revision
-            // "huggingFace": { "model": "name-of-the-default-model" } -> default model without a revision
-            // "huggingFace": { "model": "some-other-model" } -> most importantly, other model without a revision
-            this.revision = None;
-        }
-        if let Some(revision) = revision.set() {
-            this.revision = Some(revision);
-        }
         this
     }
 }
-
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr)]
-#[serde(deny_unknown_fields, rename_all = "camelCase")]
-#[deserr(rename_all = camelCase, deny_unknown_fields)]
-pub struct OpenAiEmbedderSettings {
-    #[serde(default, skip_serializing_if = "Setting::is_not_set")]
-    #[deserr(default)]
-    pub api_key: Setting<String>,
-    #[serde(default, skip_serializing_if = "Setting::is_not_set", rename = "model")]
-    #[deserr(default, rename = "model")]
-    pub embedding_model: Setting<crate::vector::openai::EmbeddingModel>,
-}
-
-impl OpenAiEmbedderSettings {
-    pub fn apply(&mut self, new: Self) {
-        let Self { api_key, embedding_model: embedding_mode } = new;
-        self.api_key.apply(api_key);
-        self.embedding_model.apply(embedding_mode);
-    }
-}
-
-impl From<crate::vector::openai::EmbedderOptions> for OpenAiEmbedderSettings {
-    fn from(value: crate::vector::openai::EmbedderOptions) -> Self {
-        Self {
-            api_key: value.api_key.map(Setting::Set).unwrap_or(Setting::Reset),
-            embedding_model: Setting::Set(value.embedding_model),
-        }
-    }
-}
-
-impl From<OpenAiEmbedderSettings> for crate::vector::openai::EmbedderOptions {
-    fn from(value: OpenAiEmbedderSettings) -> Self {
-        let OpenAiEmbedderSettings { api_key, embedding_model } = value;
-        Self { api_key: api_key.set(), embedding_model: embedding_model.set().unwrap_or_default() }
-    }
-}
-
-#[derive(Debug, Clone, Default, Serialize, Deserialize, PartialEq, Eq, Deserr)]
-#[serde(deny_unknown_fields, rename_all = "camelCase")]
-#[deserr(rename_all = camelCase, deny_unknown_fields)]
-pub struct UserProvidedSettings {
-    pub dimensions: usize,
-}
-
-impl From<UserProvidedSettings> for crate::vector::manual::EmbedderOptions {
-    fn from(value: UserProvidedSettings) -> Self {
-        Self { dimensions: value.dimensions }
-    }
-}
-
-impl From<crate::vector::manual::EmbedderOptions> for UserProvidedSettings {
-    fn from(value: crate::vector::manual::EmbedderOptions) -> Self {
-        Self { dimensions: value.dimensions }
-    }
-}