fix: Fix the issue of duplicate tool calls with identical arguments i…

crates/openfang-runtime/src/agent_loop.rs

@@ -628,7 +628,7 @@ pub async fn run_agent_loop(
 
                 // Execute each tool call with loop guard, timeout, and truncation
                 let mut tool_result_blocks = Vec::new();
-                for tool_call in &response.tool_calls {
+                for tool_call in deduplicate_tool_calls(&response) {
                     // Loop guard check
                     let verdict = loop_guard.check(&tool_call.name, &tool_call.input);
                     match &verdict {
@@ -1628,7 +1628,7 @@ pub async fn run_agent_loop_streaming(
 
                 // Execute each tool call with loop guard, timeout, and truncation
                 let mut tool_result_blocks = Vec::new();
-                for tool_call in &response.tool_calls {
+                for tool_call in deduplicate_tool_calls(&response) {
                     // Loop guard check
                     let verdict = loop_guard.check(&tool_call.name, &tool_call.input);
                     match &verdict {
@@ -2732,6 +2732,20 @@ fn try_parse_bare_json_tool_call(
     parse_json_tool_call_object(&text[..end], tool_names)
 }
 
+/// Deduplicate tool calls from the response.
+/// Returns a reference to the deduplicated tool calls.
+pub fn deduplicate_tool_calls(response: &crate::llm_driver::CompletionResponse) -> Vec<&ToolCall> {
+    let mut hash_set = std::collections::HashSet::new();
+    let mut deduplicated = Vec::new();
+    for tool_call in &response.tool_calls {
+        let hash = LoopGuard::compute_hash(&tool_call.name, &tool_call.input);
+        if hash_set.insert(hash) {
+            deduplicated.push(tool_call);
+        }
+    }
+    deduplicated
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

crates/openfang-runtime/src/loop_guard.rs

@@ -498,7 +498,7 @@ impl LoopGuard {
     }
 
     /// Compute a SHA-256 hash of the tool name and parameters.
-    fn compute_hash(tool_name: &str, params: &serde_json::Value) -> String {
+    pub fn compute_hash(tool_name: &str, params: &serde_json::Value) -> String {
         let mut hasher = Sha256::new();
         hasher.update(tool_name.as_bytes());
         hasher.update(b"|");