Respect required_providers config for all providers (#573)

- Add conditional initialization for Databricks and GoogleSheets based
on required_providers
- Extract inject_engine_guide helper to avoid duplication
- Fix ENGINE_GUIDE injection for scaffold_data_app early return
- Use match instead of if for consistency

Author: arsenyinfo

edda/edda_mcp/src/main.rs

@@ -2,7 +2,7 @@ use clap::{Parser, Subcommand};
 use edda_mcp::paths;
 use edda_mcp::providers::{
     CombinedProvider, DatabricksProvider, DeploymentProvider, GoogleSheetsProvider, IOProvider,
-    WorkspaceTools,
+    ProviderType, WorkspaceTools,
 };
 use edda_mcp::session::SessionContext;
 use edda_mcp::trajectory::TrajectoryTrackingProvider;
@@ -220,6 +220,11 @@ async fn warmup_sandbox() -> Result<()> {
     Ok(())
 }
 
+/// helper to check if provider should be enabled based on config
+fn should_enable_provider(config: &edda_mcp::config::Config, provider: ProviderType) -> bool {
+    config.required_providers.contains(&provider)
+}
+
 /// check environment configuration and prerequisites
 async fn check_environment(config: &edda_mcp::config::Config) -> Result<()> {
     use edda_mcp::providers::ProviderType;
@@ -397,22 +402,26 @@ async fn run_server(config: edda_mcp::config::Config) -> Result<()> {
     });
 
     // initialize all available providers
-    let databricks = DatabricksProvider::new().ok();
-    let deployment = if config.with_deployment {
-        DeploymentProvider::new().ok()
-    } else {
-        None
+    let databricks = match should_enable_provider(&config, ProviderType::Databricks) {
+        true => DatabricksProvider::new().ok(),
+        false => None,
+    };
+    let deployment = match config.with_deployment {
+        true => DeploymentProvider::new().ok(),
+        false => None,
+    };
+    let google_sheets = match should_enable_provider(&config, ProviderType::GoogleSheets) {
+        true => GoogleSheetsProvider::new().await.ok(),
+        false => None,
     };
-    let google_sheets = GoogleSheetsProvider::new().await.ok();
     let io = IOProvider::new(config.io_config.clone()).ok();
 
     // create session context (session_id populated earlier)
     let session_ctx = SessionContext::new(session_id.clone());
 
-    let workspace = if config.with_workspace_tools {
-        WorkspaceTools::new(session_ctx.clone()).ok()
-    } else {
-        None
+    let workspace = match config.with_workspace_tools {
+        true => WorkspaceTools::new(session_ctx.clone()).ok(),
+        false => None,
     };
 
     // print startup banner to stderr (won't interfere with stdio MCP transport)

edda/edda_mcp/src/providers/mod.rs

@@ -14,7 +14,7 @@ use crate::session::SessionContext;
 use eyre::Result;
 use rmcp::model::{
     CallToolRequestParam, CallToolResult, Implementation, PaginatedRequestParam, ProtocolVersion,
-    ServerCapabilities, ServerInfo,
+    RawContent, ServerCapabilities, ServerInfo,
 };
 use rmcp::service::{RequestContext, RoleServer};
 use rmcp::{ErrorData, ServerHandler};
@@ -38,6 +38,17 @@ enum TargetProvider {
     Workspace(Arc<WorkspaceTools>),
 }
 
+/// inject ENGINE_GUIDE into the first text content of a tool result
+fn inject_engine_guide(result: &mut CallToolResult) {
+    use crate::engine_guide::ENGINE_GUIDE;
+
+    if let Some(first_content) = result.content.first_mut() {
+        if let RawContent::Text(text_content) = &mut first_content.raw {
+            text_content.text = format!("{}\n\n---\n\n{}", ENGINE_GUIDE, text_content.text);
+        }
+    }
+}
+
 #[derive(Clone)]
 pub struct CombinedProvider {
     session_ctx: SessionContext,
@@ -302,7 +313,7 @@ impl ServerHandler for CombinedProvider {
         // intercept scaffold_data_app to set work_dir in session context
         if params.name == "scaffold_data_app" {
             if let Some(ref io) = self.io {
-                let result = io.call_tool(params.clone(), context.clone()).await?;
+                let mut result = io.call_tool(params.clone(), context.clone()).await?;
 
                 // extract work_dir from arguments and set it in session context
                 if let Some(args) = params.arguments {
@@ -319,6 +330,10 @@ impl ServerHandler for CombinedProvider {
                     }
                 }
 
+                if is_first_call {
+                    inject_engine_guide(&mut result);
+                }
+
                 return Ok(result);
             }
         }
@@ -331,17 +346,8 @@ impl ServerHandler for CombinedProvider {
             TargetProvider::Workspace(provider) => provider.call_tool(params, context).await,
         }?;
 
-        // inject engine guide on first tool call
         if is_first_call {
-            use crate::engine_guide::ENGINE_GUIDE;
-            use rmcp::model::RawContent;
-
-            // prepend engine guide to the first content item
-            if let Some(first_content) = result.content.first_mut() {
-                if let RawContent::Text(text_content) = &mut first_content.raw {
-                    text_content.text = format!("{}\n\n---\n\n{}", ENGINE_GUIDE, text_content.text);
-                }
-            }
+            inject_engine_guide(&mut result);
         }
 
         Ok(result)