Put tool payload capture config under plugin namespace

Signed-off-by: Eric Peterson <ericpeterson@spotify.com>

docs/ai/mcp-actions.md

@@ -326,13 +326,13 @@ This flag is honored by every plugin that creates spans through the [Tracing Ser
 
 ### Capturing tool arguments and results
 
-When `backend.tracing.capture.mcpActionsToolPayloads` is enabled, the tool's input arguments and output result are recorded on the span as `gen_ai.tool.call.arguments` and `gen_ai.tool.call.result`.
+When `mcpActions.tracing.capture.toolPayload` is enabled, the tool's input arguments and output result are recorded on the span as `gen_ai.tool.call.arguments` and `gen_ai.tool.call.result`.
 
 ```yaml title="app-config.yaml"
-backend:
+mcpActions:
   tracing:
     capture:
-      mcpActionsToolPayloads: true # defaults to false
+      toolPayload: true # defaults to false
 ```
 
 :::warning

plugins/mcp-actions-backend/config.d.ts

@@ -15,23 +15,6 @@
  */
 
 export interface Config {
-  backend?: {
-    tracing?: {
-      capture?: {
-        /**
-         * When true, the MCP tool call's input arguments and output result
-         * are included on the MCP `tools/call` server span as
-         * `gen_ai.tool.call.arguments` and `gen_ai.tool.call.result`.
-         * These attributes are marked Opt-In by the OpenTelemetry GenAI
-         * semantic conventions because they may contain sensitive
-         * information (entity payloads, scaffolder inputs, free-form
-         * text). Defaults to false.
-         */
-        mcpActionsToolPayloads?: boolean;
-      };
-    };
-  };
-
   mcpActions?: {
     /**
      * Display name for the MCP server. Defaults to "backstage".
@@ -53,6 +36,21 @@ export interface Config {
      */
     namespacedToolNames?: boolean;
 
+    tracing?: {
+      capture?: {
+        /**
+         * When true, the MCP tool call's input arguments and output result
+         * are included on the MCP `tools/call` server span as
+         * `gen_ai.tool.call.arguments` and `gen_ai.tool.call.result`.
+         * These attributes are marked Opt-In by the OpenTelemetry GenAI
+         * semantic conventions because they may contain sensitive
+         * information (entity payloads, scaffolder inputs, free-form
+         * text). Defaults to false.
+         */
+        toolPayload?: boolean;
+      };
+    };
+
     /**
      * Named MCP servers, each exposed at /api/mcp-actions/v1/{key}.
      * When not configured, the plugin serves a single server at /api/mcp-actions/v1.

plugins/mcp-actions-backend/src/plugin.ts

@@ -68,9 +68,8 @@ export const mcpPlugin = createBackendPlugin({
           'mcpActions.namespacedToolNames',
         );
         const captureToolPayloads =
-          config.getOptionalBoolean(
-            'backend.tracing.capture.mcpActionsToolPayloads',
-          ) ?? false;
+          config.getOptionalBoolean('mcpActions.tracing.capture.toolPayload') ??
+          false;
 
         const mcpService = await McpService.create({
           actions,