added mermaid pr suggestion

Author: Prashant-7718

packages/sdk/src/index.test.ts

@@ -171,4 +171,42 @@ describe('MermaidChart', () => {
       ).rejects.toThrow(AICreditsLimitExceededError);
     });
   });
+
+  describe('#mermaidPrSuggestion', () => {
+    beforeEach(async () => {
+      await client.setAccessToken('test-access-token');
+    });
+
+    it('should return title and description from diagram diff', async () => {
+      vi.spyOn(client, 'mermaidPrSuggestion').mockResolvedValue({
+        title: 'Add validation step to flowchart',
+        description: '## What changed\n- Added node C',
+      });
+
+      const result = await client.mermaidPrSuggestion({
+        originalDiagram: 'flowchart TD\n  A --> B',
+        editedDiagram: 'flowchart TD\n  A --> B\n  B --> C[Validate]',
+      });
+
+      expect(result.title).toContain('validation');
+      expect(result.description).toContain('What changed');
+    });
+
+    it('should throw AICreditsLimitExceededError on 402', async () => {
+      // eslint-disable-next-line @typescript-eslint/no-explicit-any
+      vi.spyOn((client as any).axios, 'post').mockRejectedValue({
+        response: {
+          status: 402,
+          data: 'AI credits limit exceeded',
+        },
+      });
+
+      await expect(
+        client.mermaidPrSuggestion({
+          originalDiagram: 'flowchart TD\n  A --> B',
+          editedDiagram: 'flowchart TD\n  A --> B\n  B --> C',
+        }),
+      ).rejects.toThrow(AICreditsLimitExceededError);
+    });
+  });
 });

packages/sdk/src/index.ts

@@ -19,6 +19,8 @@ import type {
   MCUser,
   RepairDiagramRequest,
   RepairDiagramResponse,
+  MermaidPrSuggestionRequest,
+  MermaidPrSuggestionResponse,
   AICreditsUsage,
 } from './types.js';
 import { URLS } from './urls.js';
@@ -330,6 +332,24 @@ export class MermaidChart {
     }
   }
 
+  /**
+   * Suggests a pull request title and body (markdown) from a before/after diagram diff (Mermaid AI).
+   *
+   * @param request - `originalDiagram` and `editedDiagram` only
+   * @throws {@link AICreditsLimitExceededError} if credits limit exceeded (HTTP 402)
+   */
+  public async mermaidPrSuggestion(request: MermaidPrSuggestionRequest): Promise<MermaidPrSuggestionResponse> {
+    try {
+      const response = await this.axios.post<MermaidPrSuggestionResponse>(
+        URLS.rest.openai.prSummary,
+        request,
+      );
+      return response.data;
+    } catch (error: unknown) {
+      throwIfAICreditsExceeded(error);
+    }
+  }
+
   /**
    * Chat with Mermaid AI about a diagram.
    *

packages/sdk/src/types.ts

@@ -96,6 +96,22 @@ export interface RepairDiagramRequest {
   userID?: string;
 }
 
+/**
+ * Only the two diagram versions are sent; the server derives user plan and usage from the session.
+ */
+export interface MermaidPrSuggestionRequest {
+  originalDiagram: string;
+  editedDiagram: string;
+}
+
+/**
+ * Public response: suggested PR title and markdown description
+ */
+export interface MermaidPrSuggestionResponse {
+  title: string;
+  description: string;
+}
+
 /**
  * Request parameters for chatting with the Mermaid AI about a diagram.
  */

packages/sdk/src/urls.ts

@@ -41,6 +41,7 @@ export const URLS = {
     },
     openai: {
       repair: `/rest-api/openai/repair`,
+      prSummary: `/rest-api/openai/pr-summary`,
       chat: `/rest-api/openai/chat`,
     },
   },