anthropic: Allow specifying additional beta headers for custom models (#20551)

Release Notes:

- Added the ability to specify additional beta headers for custom
Anthropic models.

---------

Co-authored-by: David Soria Parra <167242713+dsp-ant@users.noreply.github.com>
Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>

crates/anthropic/src/anthropic.rs

@@ -50,6 +50,8 @@ pub enum Model {
         cache_configuration: Option<AnthropicModelCacheConfiguration>,
         max_output_tokens: Option<u32>,
         default_temperature: Option<f32>,
+        #[serde(default)]
+        extra_beta_headers: Vec<String>,
     },
 }
 
@@ -146,6 +148,24 @@ impl Model {
         }
     }
 
+    pub fn beta_headers(&self) -> String {
+        let mut headers = vec!["prompt-caching-2024-07-31".to_string()];
+
+        if let Self::Custom {
+            extra_beta_headers, ..
+        } = self
+        {
+            headers.extend(
+                extra_beta_headers
+                    .iter()
+                    .filter(|header| !header.trim().is_empty())
+                    .cloned(),
+            );
+        }
+
+        headers.join(",")
+    }
+
     pub fn tool_model_id(&self) -> &str {
         if let Self::Custom {
             tool_override: Some(tool_override),
@@ -166,11 +186,12 @@ pub async fn complete(
     request: Request,
 ) -> Result<Response, AnthropicError> {
     let uri = format!("{api_url}/v1/messages");
+    let model = Model::from_id(&request.model)?;
     let request_builder = HttpRequest::builder()
         .method(Method::POST)
         .uri(uri)
         .header("Anthropic-Version", "2023-06-01")
-        .header("Anthropic-Beta", "prompt-caching-2024-07-31")
+        .header("Anthropic-Beta", model.beta_headers())
         .header("X-Api-Key", api_key)
         .header("Content-Type", "application/json");
 
@@ -281,14 +302,12 @@ pub async fn stream_completion_with_rate_limit_info(
         stream: true,
     };
     let uri = format!("{api_url}/v1/messages");
+    let model = Model::from_id(&request.base.model)?;
     let request_builder = HttpRequest::builder()
         .method(Method::POST)
         .uri(uri)
         .header("Anthropic-Version", "2023-06-01")
-        .header(
-            "Anthropic-Beta",
-            "tools-2024-04-04,prompt-caching-2024-07-31,max-tokens-3-5-sonnet-2024-07-15",
-        )
+        .header("Anthropic-Beta", model.beta_headers())
         .header("X-Api-Key", api_key)
         .header("Content-Type", "application/json");
     let serialized_request =

crates/language_models/src/provider/anthropic.rs

@@ -52,6 +52,8 @@ pub struct AvailableModel {
     pub cache_configuration: Option<LanguageModelCacheConfiguration>,
     pub max_output_tokens: Option<u32>,
     pub default_temperature: Option<f32>,
+    #[serde(default)]
+    pub extra_beta_headers: Vec<String>,
 }
 
 pub struct AnthropicLanguageModelProvider {
@@ -202,6 +204,7 @@ impl LanguageModelProvider for AnthropicLanguageModelProvider {
                     }),
                     max_output_tokens: model.max_output_tokens,
                     default_temperature: model.default_temperature,
+                    extra_beta_headers: model.extra_beta_headers.clone(),
                 },
             );
         }

crates/language_models/src/provider/cloud.rs

@@ -94,6 +94,9 @@ pub struct AvailableModel {
     pub cache_configuration: Option<LanguageModelCacheConfiguration>,
     /// The default temperature to use for this model.
     pub default_temperature: Option<f32>,
+    /// Any extra beta headers to provide when using the model.
+    #[serde(default)]
+    pub extra_beta_headers: Vec<String>,
 }
 
 struct GlobalRefreshLlmTokenListener(Model<RefreshLlmTokenListener>);
@@ -323,6 +326,7 @@ impl LanguageModelProvider for CloudLanguageModelProvider {
                     }),
                     default_temperature: model.default_temperature,
                     max_output_tokens: model.max_output_tokens,
+                    extra_beta_headers: model.extra_beta_headers.clone(),
                 }),
                 AvailableProvider::OpenAi => CloudModel::OpenAi(open_ai::Model::Custom {
                     name: model.name.clone(),

crates/language_models/src/settings.rs

@@ -97,6 +97,7 @@ impl AnthropicSettingsContent {
                                     cache_configuration,
                                     max_output_tokens,
                                     default_temperature,
+                                    extra_beta_headers,
                                 } => Some(provider::anthropic::AvailableModel {
                                     name,
                                     display_name,
@@ -111,6 +112,7 @@ impl AnthropicSettingsContent {
                                     ),
                                     max_output_tokens,
                                     default_temperature,
+                                    extra_beta_headers,
                                 }),
                                 _ => None,
                             })