fix: handles tool validation errors (#651)

Author: dingfeli

crates/q_cli/src/cli/chat/mod.rs

@@ -468,6 +468,29 @@ Hi, I'm <g>Amazon Q</g>. I can answer questions about your workspace and tooling
             // If we have any validation errors, then return them immediately to the model.
             if !tool_results.is_empty() {
                 debug!(?tool_results, "Error found in the model tools");
+                queue!(
+                    self.output,
+                    style::SetAttribute(Attribute::Bold),
+                    style::Print("Tool validation failed: "),
+                    style::SetAttribute(Attribute::Reset),
+                )?;
+                for tool_result in &tool_results {
+                    for block in &tool_result.content {
+                        let content = match block {
+                            ToolResultContentBlock::Text(t) => Some(t.as_str()),
+                            ToolResultContentBlock::Json(d) => d.as_string(),
+                        };
+                        if let Some(content) = content {
+                            queue!(
+                                self.output,
+                                style::Print("\n"),
+                                style::SetForegroundColor(Color::Red),
+                                style::Print(format!("{}\n", content)),
+                                style::SetForegroundColor(Color::Reset),
+                            )?;
+                        }
+                    }
+                }
                 self.conversation_state.add_tool_results(tool_results);
                 self.send_tool_use_telemetry().await;
                 return Ok(Some(

crates/q_cli/src/cli/chat/tools/mod.rs

@@ -83,7 +83,7 @@ impl TryFrom<ToolUse> for Tool {
         let map_err = |parse_error| ToolResult {
             tool_use_id: value.id.clone(),
             content: vec![ToolResultContentBlock::Text(format!(
-                "failed to deserialize with the following error: {parse_error}"
+                "Failed to validate tool parameters: {parse_error}. The model has either suggested tool parameters which are incompatible with the existing tools, or has suggested one or more tool that does not exist in the list of known tools."
             ))],
             status: ToolResultStatus::Error,
         };