perf: optimize workflow tool responses for token efficiency (v2.29.0) (#479)

* perf: optimize workflow tool responses for token efficiency (v2.29.0)

Reduce response sizes by 75-90% for 4 workflow management tools:

- n8n_update_partial_workflow: Returns {id, name, active, operationsApplied}
- n8n_create_workflow: Returns {id, name, active, nodeCount}
- n8n_update_full_workflow: Returns {id, name, active, nodeCount}
- n8n_delete_workflow: Returns {id, name, deleted: true}

AI agents can use n8n_get_workflow with mode 'structure' if they need
to verify the current workflow state after operations.

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix: update tests and add nodeCount to partial update response

- Fix handleCreateWorkflow test to expect minimal response
- Fix handleDeleteWorkflow test to expect minimal response
- Add nodeCount to n8n_update_partial_workflow response for consistency
- Update documentation and CHANGELOG

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix: update handlers-workflow-diff tests for minimal response

Update 3 more tests that expected full workflow in response:
- should apply diff operations successfully
- should activate workflow after successful update
- should deactivate workflow after successful update

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix: update integration tests to use minimal response format

Integration tests now verify minimal response format and use
client.getWorkflow() to fetch actual workflow state for verification.

Conceived by Romuald Czlonkowski - www.aiadvisors.pl/en

* fix: update create/update workflow integration tests for minimal response

Integration tests now verify minimal response and use client.getWorkflow()
to fetch actual workflow state for detailed verification.

Conceived by Romuald Czlonkowski - www.aiadvisors.pl/en

* fix: add type assertions to fix TypeScript errors in tests

Conceived by Romuald Czlonkowski - www.aiadvisors.pl/en

---------

Co-authored-by: Romuald Członkowski <romualdczlonkowski@MacBook-Pro-Romuald.local>
Co-authored-by: Claude <noreply@anthropic.com>

src/mcp/handlers-n8n-manager.ts

@@ -518,8 +518,13 @@ export async function handleCreateWorkflow(args: unknown, context?: InstanceCont
 
     return {
       success: true,
-      data: workflow,
-      message: `Workflow "${workflow.name}" created successfully with ID: ${workflow.id}`
+      data: {
+        id: workflow.id,
+        name: workflow.name,
+        active: workflow.active,
+        nodeCount: workflow.nodes?.length || 0
+      },
+      message: `Workflow "${workflow.name}" created successfully with ID: ${workflow.id}. Use n8n_get_workflow with mode 'structure' to verify current state.`
     };
   } catch (error) {
     if (error instanceof z.ZodError) {
@@ -813,8 +818,13 @@ export async function handleUpdateWorkflow(
 
     return {
       success: true,
-      data: workflow,
-      message: `Workflow "${workflow.name}" updated successfully`
+      data: {
+        id: workflow.id,
+        name: workflow.name,
+        active: workflow.active,
+        nodeCount: workflow.nodes?.length || 0
+      },
+      message: `Workflow "${workflow.name}" updated successfully. Use n8n_get_workflow with mode 'structure' to verify current state.`
     };
   } catch (error) {
     // Track failed mutation
@@ -880,8 +890,12 @@ export async function handleDeleteWorkflow(args: unknown, context?: InstanceCont
 
     return {
       success: true,
-      data: deleted,
-      message: `Workflow ${id} deleted successfully`
+      data: {
+        id: deleted?.id || id,
+        name: deleted?.name,
+        deleted: true
+      },
+      message: `Workflow "${deleted?.name || id}" deleted successfully.`
     };
   } catch (error) {
     if (error instanceof z.ZodError) {

src/mcp/handlers-workflow-diff.ts

@@ -363,13 +363,15 @@ export async function handleUpdatePartialWorkflow(
 
       return {
         success: true,
-        data: finalWorkflow,
-        message: `Workflow "${finalWorkflow.name}" updated successfully. Applied ${diffResult.operationsApplied} operations.${activationMessage}`,
-        details: {
-          operationsApplied: diffResult.operationsApplied,
-          workflowId: finalWorkflow.id,
-          workflowName: finalWorkflow.name,
+        data: {
+          id: finalWorkflow.id,
+          name: finalWorkflow.name,
           active: finalWorkflow.active,
+          nodeCount: finalWorkflow.nodes?.length || 0,
+          operationsApplied: diffResult.operationsApplied
+        },
+        message: `Workflow "${finalWorkflow.name}" updated successfully. Applied ${diffResult.operationsApplied} operations.${activationMessage} Use n8n_get_workflow with mode 'structure' to verify current state.`,
+        details: {
           applied: diffResult.applied,
           failed: diffResult.failed,
           errors: diffResult.errors,

src/mcp/tool-docs/workflow_management/n8n-create-workflow.ts

@@ -23,7 +23,7 @@ export const n8nCreateWorkflowDoc: ToolDocumentation = {
       connections: { type: 'object', required: true, description: 'Node connections. Keys are source node IDs' },
       settings: { type: 'object', description: 'Optional workflow settings (timezone, error handling, etc.)' }
     },
-    returns: 'Created workflow object with id, name, nodes, connections, active status',
+    returns: 'Minimal summary (id, name, active, nodeCount) for token efficiency. Use n8n_get_workflow with mode "structure" to verify current state if needed.',
     examples: [
       `// Basic webhook to Slack workflow
 n8n_create_workflow({

src/mcp/tool-docs/workflow_management/n8n-delete-workflow.ts

@@ -19,7 +19,7 @@ export const n8nDeleteWorkflowDoc: ToolDocumentation = {
     parameters: {
       id: { type: 'string', required: true, description: 'Workflow ID to delete permanently' }
     },
-    returns: 'Success confirmation or error if workflow not found/cannot be deleted',
+    returns: 'Minimal confirmation (id, name, deleted: true) for token efficiency.',
     examples: [
       'n8n_delete_workflow({id: "abc123"}) - Delete specific workflow',
       'if (confirm) { n8n_delete_workflow({id: wf.id}); } // With confirmation'

src/mcp/tool-docs/workflow_management/n8n-update-full-workflow.ts

@@ -25,7 +25,7 @@ export const n8nUpdateFullWorkflowDoc: ToolDocumentation = {
       settings: { type: 'object', description: 'Workflow settings to update (timezone, error handling, etc.)' },
       intent: { type: 'string', description: 'Intent of the change - helps to return better response. Include in every tool call. Example: "Migrate workflow to new node versions".' }
     },
-    returns: 'Updated workflow object with all fields including the changes applied',
+    returns: 'Minimal summary (id, name, active, nodeCount) for token efficiency. Use n8n_get_workflow with mode "structure" to verify current state if needed.',
     examples: [
       'n8n_update_full_workflow({id: "abc", intent: "Rename workflow for clarity", name: "New Name"}) - Rename with intent',
       'n8n_update_full_workflow({id: "abc", name: "New Name"}) - Rename only',

src/mcp/tool-docs/workflow_management/n8n-update-partial-workflow.ts

@@ -312,7 +312,7 @@ n8n_update_partial_workflow({
       continueOnError: { type: 'boolean', description: 'If true, apply valid operations even if some fail (best-effort mode). Returns applied and failed operation indices. Default: false (atomic)' },
       intent: { type: 'string', description: 'Intent of the change - helps to return better response. Include in every tool call. Example: "Add error handling for API failures".' }
     },
-    returns: 'Updated workflow object or validation results if validateOnly=true',
+    returns: 'Minimal summary (id, name, active, nodeCount, operationsApplied) for token efficiency. Use n8n_get_workflow with mode "structure" to verify current state if needed. Returns validation results if validateOnly=true.',
     examples: [
       '// Include intent parameter for better responses\nn8n_update_partial_workflow({id: "abc", intent: "Add error handling for API failures", operations: [{type: "addConnection", source: "HTTP Request", target: "Error Handler"}]})',
       '// Add a basic node (minimal configuration)\nn8n_update_partial_workflow({id: "abc", operations: [{type: "addNode", node: {name: "Process Data", type: "n8n-nodes-base.set", position: [400, 300], parameters: {}}}]})',