fix: resolve MCP array serialization schema issue

- Remove transform functions from array schemas in common.ts and issues.ts
- Add JSON string parsing logic to handlers before schema validation
- Preserve backward compatibility by accepting both arrays and JSON strings

This fixes the issue where MCP clients receive incomplete schemas that
don't include the string option for array parameters, causing validation
errors when clients send JSON-serialized arrays.

Author: shadowyman

src/index.ts

@@ -146,6 +146,22 @@ export {
   handleSonarQubeUpdateHotspotStatus,
 } from './handlers/index.js';
 
+// Helper function to parse JSON string arrays in parameters
+function parseArrayParameters(params: Record<string, unknown>, paramNames: string[]): void {
+  for (const key of paramNames) {
+    if (typeof params[key] === 'string') {
+      try {
+        const parsed = JSON.parse(params[key] as string);
+        if (Array.isArray(parsed)) {
+          params[key] = parsed;
+        }
+      } catch {
+        // Not valid JSON, keep as string for backward compatibility
+      }
+    }
+  }
+}
+
 // Lambda functions for the MCP tools
 /**
  * Lambda function for projects tool
@@ -166,6 +182,16 @@ export const metricsHandler = async (params: { page: number | null; page_size: n
  * Lambda function for issues tool
  */
 export const issuesHandler = async (params: Record<string, unknown>) => {
+  // Parse JSON strings to arrays for array parameters
+  parseArrayParameters(params, [
+    'projects', 'component_keys', 'components', 'directories', 'files', 
+    'scopes', 'issues', 'severities', 'statuses', 'resolutions', 'types',
+    'clean_code_attribute_categories', 'impact_severities', 'impact_software_qualities',
+    'issue_statuses', 'rules', 'tags', 'assignees', 'authors', 'cwe',
+    'owasp_top10', 'owasp_top10_v2021', 'sans_top25', 'sonarsource_security',
+    'sonarsource_security_category', 'languages', 'facets', 'additional_fields'
+  ]);
+  
   return handleSonarQubeGetIssues(mapToSonarQubeParams(params));
 };
 

src/schemas/common.ts

@@ -13,102 +13,40 @@ export const severitySchema = z
 
 export const severitiesSchema = z
   .union([z.array(z.enum(['INFO', 'MINOR', 'MAJOR', 'CRITICAL', 'BLOCKER'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid severities
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) => ['INFO', 'MINOR', 'MAJOR', 'CRITICAL', 'BLOCKER'].includes(v));
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 
 // Status schemas
 export const statusSchema = z
   .union([z.array(z.enum(['OPEN', 'CONFIRMED', 'REOPENED', 'RESOLVED', 'CLOSED'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid statuses
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) =>
-        ['OPEN', 'CONFIRMED', 'REOPENED', 'RESOLVED', 'CLOSED'].includes(v)
-      );
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 
 // Resolution schemas
 export const resolutionSchema = z
   .union([z.array(z.enum(['FALSE-POSITIVE', 'WONTFIX', 'FIXED', 'REMOVED'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid resolutions
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) => ['FALSE-POSITIVE', 'WONTFIX', 'FIXED', 'REMOVED'].includes(v));
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 
 // Type schemas
 export const typeSchema = z
   .union([z.array(z.enum(['CODE_SMELL', 'BUG', 'VULNERABILITY', 'SECURITY_HOTSPOT'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid types
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) =>
-        ['CODE_SMELL', 'BUG', 'VULNERABILITY', 'SECURITY_HOTSPOT'].includes(v)
-      );
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 
 // Clean Code taxonomy schemas
 export const cleanCodeAttributeCategoriesSchema = z
   .union([z.array(z.enum(['ADAPTABLE', 'CONSISTENT', 'INTENTIONAL', 'RESPONSIBLE'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid categories
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) =>
-        ['ADAPTABLE', 'CONSISTENT', 'INTENTIONAL', 'RESPONSIBLE'].includes(v)
-      );
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 
 export const impactSeveritiesSchema = z
   .union([z.array(z.enum(['HIGH', 'MEDIUM', 'LOW'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid impact severities
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) => ['HIGH', 'MEDIUM', 'LOW'].includes(v));
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 
 export const impactSoftwareQualitiesSchema = z
   .union([z.array(z.enum(['MAINTAINABILITY', 'RELIABILITY', 'SECURITY'])), z.string()])
-  .transform((val) => {
-    const parsed = parseJsonStringArray(val);
-    // Validate that all values are valid software qualities
-    if (parsed && Array.isArray(parsed)) {
-      return parsed.filter((v) => ['MAINTAINABILITY', 'RELIABILITY', 'SECURITY'].includes(v));
-    }
-    return parsed;
-  })
   .nullable()
   .optional();
 

src/schemas/issues.ts

@@ -130,21 +130,18 @@ export const issuesToolSchema = {
   project_key: z.string().optional().describe('Single project key for backward compatibility'), // Made optional to support projects array
   projects: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe('Filter by project keys'),
   component_keys: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe(
       'Filter by component keys (file paths, directories, or modules). Use this to filter issues by specific files or folders'
     ),
   components: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe('Alias for component_keys - filter by file paths, directories, or modules'),
@@ -155,26 +152,16 @@ export const issuesToolSchema = {
     .describe('Return only issues on the specified components, not on their sub-components'),
   directories: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe('Filter by directory paths'),
   files: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe('Filter by specific file paths'),
   scopes: z
     .union([z.array(z.enum(['MAIN', 'TEST', 'OVERALL'])), z.string()])
-    .transform((val) => {
-      const parsed = parseJsonStringArray(val);
-      // Validate that all values are valid scopes
-      if (parsed && Array.isArray(parsed)) {
-        return parsed.filter((v) => ['MAIN', 'TEST', 'OVERALL'].includes(v));
-      }
-      return parsed;
-    })
     .nullable()
     .optional()
     .describe('Filter by issue scopes (MAIN, TEST, OVERALL)'),
@@ -186,7 +173,6 @@ export const issuesToolSchema = {
   // Issue filters
   issues: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
   severity: severitySchema, // Deprecated single value
@@ -208,13 +194,11 @@ export const issuesToolSchema = {
   // Rules and tags
   rules: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe('Filter by rule keys'),
   tags: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe(
@@ -235,7 +219,6 @@ export const issuesToolSchema = {
     .describe('Filter to only assigned (true) or unassigned (false) issues'),
   assignees: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe(
@@ -244,54 +227,45 @@ export const issuesToolSchema = {
   author: z.string().nullable().optional().describe('Filter by single issue author'), // Single author
   authors: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe('Filter by multiple issue authors'), // Multiple authors
 
   // Security standards
   cwe: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
   owasp_top10: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
   owasp_top10_v2021: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(), // New 2021 version
   sans_top25: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
   sonarsource_security: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
   sonarsource_security_category: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
 
   // Languages
   languages: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),
 
   // Facets
   facets: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional()
     .describe(
@@ -325,7 +299,6 @@ export const issuesToolSchema = {
   // Response optimization
   additional_fields: z
     .union([z.array(z.string()), z.string()])
-    .transform(parseJsonStringArray)
     .nullable()
     .optional(),