feat(runtime): add reasoning toggle for ollama

src/providers/ollama.rs

@@ -7,6 +7,7 @@ use std::collections::HashMap;
 pub struct OllamaProvider {
     base_url: String,
     api_key: Option<String>,
+    reasoning_enabled: Option<bool>,
 }
 
 // ─── Request Structures ───────────────────────────────────────────────────────
@@ -18,6 +19,8 @@ struct ChatRequest {
     stream: bool,
     options: Options,
     #[serde(skip_serializing_if = "Option::is_none")]
+    think: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     tools: Option<Vec<serde_json::Value>>,
 }
 
@@ -85,6 +88,14 @@ struct OllamaFunction {
 
 impl OllamaProvider {
     pub fn new(base_url: Option<&str>, api_key: Option<&str>) -> Self {
+        Self::new_with_reasoning(base_url, api_key, None)
+    }
+
+    pub fn new_with_reasoning(
+        base_url: Option<&str>,
+        api_key: Option<&str>,
+        reasoning_enabled: Option<bool>,
+    ) -> Self {
         let api_key = api_key.and_then(|value| {
             let trimmed = value.trim();
             (!trimmed.is_empty()).then(|| trimmed.to_string())
@@ -96,6 +107,7 @@ impl OllamaProvider {
                 .trim_end_matches('/')
                 .to_string(),
             api_key,
+            reasoning_enabled,
         }
     }
 
@@ -137,6 +149,23 @@ impl OllamaProvider {
         serde_json::from_str(arguments).unwrap_or_else(|_| serde_json::json!({}))
     }
 
+    fn build_chat_request(
+        &self,
+        messages: Vec<Message>,
+        model: &str,
+        temperature: f64,
+        tools: Option<&[serde_json::Value]>,
+    ) -> ChatRequest {
+        ChatRequest {
+            model: model.to_string(),
+            messages,
+            stream: false,
+            options: Options { temperature },
+            think: self.reasoning_enabled,
+            tools: tools.map(|t| t.to_vec()),
+        }
+    }
+
     /// Convert internal chat history format to Ollama's native tool-call message schema.
     ///
     /// `run_tool_call_loop` stores native assistant/tool entries as JSON strings in
@@ -235,22 +264,17 @@ impl OllamaProvider {
         should_auth: bool,
         tools: Option<&[serde_json::Value]>,
     ) -> anyhow::Result<ApiChatResponse> {
-        let request = ChatRequest {
-            model: model.to_string(),
-            messages,
-            stream: false,
-            options: Options { temperature },
-            tools: tools.map(|t| t.to_vec()),
-        };
+        let request = self.build_chat_request(messages, model, temperature, tools);
 
         let url = format!("{}/api/chat", self.base_url);
 
         tracing::debug!(
-            "Ollama request: url={} model={} message_count={} temperature={} tool_count={}",
+            "Ollama request: url={} model={} message_count={} temperature={} think={:?} tool_count={}",
             url,
             model,
             request.messages.len(),
             temperature,
+            request.think,
             request.tools.as_ref().map_or(0, |t| t.len()),
         );
 
@@ -645,6 +669,44 @@ mod tests {
         assert!(!should_auth);
     }
 
+    #[test]
+    fn request_omits_think_when_reasoning_not_configured() {
+        let provider = OllamaProvider::new(None, None);
+        let request = provider.build_chat_request(
+            vec![Message {
+                role: "user".to_string(),
+                content: Some("hello".to_string()),
+                tool_calls: None,
+                tool_name: None,
+            }],
+            "llama3",
+            0.7,
+            None,
+        );
+
+        let json = serde_json::to_value(request).unwrap();
+        assert!(json.get("think").is_none());
+    }
+
+    #[test]
+    fn request_includes_think_when_reasoning_configured() {
+        let provider = OllamaProvider::new_with_reasoning(None, None, Some(false));
+        let request = provider.build_chat_request(
+            vec![Message {
+                role: "user".to_string(),
+                content: Some("hello".to_string()),
+                tool_calls: None,
+                tool_name: None,
+            }],
+            "llama3",
+            0.7,
+            None,
+        );
+
+        let json = serde_json::to_value(request).unwrap();
+        assert_eq!(json.get("think"), Some(&serde_json::json!(false)));
+    }
+
     #[test]
     fn response_deserializes() {
         let json = r#"{"message":{"role":"assistant","content":"Hello from Ollama!"}}"#;