fix: use JSON Schema Draft-07 for MCP tool schemas to support VSCode/Copilot

Author: DaleSeo

crates/apollo-mcp-server/src/introspection/tools/validate.rs

@@ -11,7 +11,6 @@ use rmcp::schemars::JsonSchema;
 use rmcp::serde_json::Value;
 use rmcp::{schemars, serde_json};
 use serde::Deserialize;
-use std::default::Default;
 use std::sync::Arc;
 use tokio::sync::Mutex;
 

crates/apollo-mcp-server/src/json_schema.rs

@@ -2,9 +2,47 @@
 #[macro_export]
 macro_rules! schema_from_type {
     ($type:ty) => {{
-        match serde_json::to_value(schemars::schema_for!($type)) {
+        // Use Draft-07 for compatibility with MCP clients like VSCode/Copilot that don't support newer drafts.
+        // See: https://github.com/microsoft/vscode/issues/251315
+        let settings = schemars::generate::SchemaSettings::draft07();
+        let generator = settings.into_generator();
+        let schema = generator.into_root_schema_for::<$type>();
+        match serde_json::to_value(schema) {
             Ok(Value::Object(schema)) => schema,
             _ => panic!("Failed to generate schema for {}", stringify!($type)),
         }
     }};
 }
+
+#[cfg(test)]
+mod tests {
+    use schemars::JsonSchema;
+    use serde::Deserialize;
+    use serde_json::Value;
+
+    #[derive(JsonSchema, Deserialize)]
+    struct TestInput {
+        #[allow(dead_code)]
+        field: String,
+    }
+
+    #[test]
+    fn test_schema_from_type() {
+        let schema = schema_from_type!(TestInput);
+
+        assert_eq!(
+            serde_json::to_value(&schema).unwrap(),
+            serde_json::json!({
+                "$schema": "http://json-schema.org/draft-07/schema#",
+                "title": "TestInput",
+                "type": "object",
+                "properties": {
+                    "field": {
+                        "type": "string"
+                    }
+                },
+                "required": ["field"]
+            })
+        );
+    }
+}