diff --git a/.github/workflows/api-validation.yml b/.github/workflows/api-validation.yml
new file mode 100644
index 0000000..8bcd5db
--- /dev/null
+++ b/.github/workflows/api-validation.yml
@@ -0,0 +1,40 @@
+name: API & Schema Validation
+
+permissions:
+  contents: read
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+concurrency:
+  group: api-validation-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
+        with:
+          persist-credentials: false
+
+      - name: Setup Node.js
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020
+        with:
+          node-version: 22
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run API & Schema Validation
+        run: npm run validate-api
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/build-matrix.yml b/.github/workflows/build-matrix.yml
new file mode 100644
index 0000000..75535b4
--- /dev/null
+++ b/.github/workflows/build-matrix.yml
@@ -0,0 +1,40 @@
+name: Build Matrix CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+concurrency:
+  group: build-matrix-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build:
+    name: Build (Node ${{ matrix.node-version }} on ${{ matrix.os }})
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+        node-version: [20, 22]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build application
+        run: npm run build
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..e7309f3
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,14 @@
+# Makefile for OrgExplorer API & Schema Validation
+
+.PHONY: install validate-api test
+
+# Install project and development dependencies
+install:
+	npm install
+
+# Run the GraphQL and REST API schema validation script
+validate-api:
+	npm run validate-api
+
+# Alias for validation (useful in generic test runner context)
+test: validate-api
diff --git a/package-lock.json b/package-lock.json
index 29676f9..f300c73 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -18,8 +18,12 @@
         "tailwindcss": "^4.3.0"
       },
       "devDependencies": {
+        "@octokit/graphql-schema": "^15.26.1",
         "@vitejs/plugin-react": "^4.3.1",
-        "vite": "^5.4.6"
+        "dotenv": "^17.4.2",
+        "graphql": "^17.0.2",
+        "vite": "^5.4.6",
+        "zod": "^4.4.3"
       }
     },
     "node_modules/@babel/code-frame": {
@@ -726,6 +730,27 @@
         "@jridgewell/sourcemap-codec": "^1.4.14"
       }
     },
+    "node_modules/@octokit/graphql-schema": {
+      "version": "15.26.1",
+      "resolved": "https://registry.npmjs.org/@octokit/graphql-schema/-/graphql-schema-15.26.1.tgz",
+      "integrity": "sha512-RFDC2MpRBd4AxSRvUeBIVeBU7ojN/SxDfALUd7iVYOSeEK3gZaqR2MGOysj4Zh2xj2RY5fQAUT+Oqq7hWTraMA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "graphql": "^16.0.0",
+        "graphql-tag": "^2.10.3"
+      }
+    },
+    "node_modules/@octokit/graphql-schema/node_modules/graphql": {
+      "version": "16.14.2",
+      "resolved": "https://registry.npmjs.org/graphql/-/graphql-16.14.2.tgz",
+      "integrity": "sha512-Chq1s4CY7jmh8gO2qvLIJyfCDIN+EHLFW/9iShnp1z8FjBQMoodWP1kDC36VAMXXIvAjj4ARa7ntfAV2BrjsbA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^12.22.0 || ^14.16.0 || ^16.0.0 || >=17.0.0"
+      }
+    },
     "node_modules/@remix-run/router": {
       "version": "1.23.2",
       "resolved": "https://registry.npmjs.org/@remix-run/router/-/router-1.23.2.tgz",
@@ -2011,6 +2036,19 @@
         "csstype": "^3.0.2"
       }
     },
+    "node_modules/dotenv": {
+      "version": "17.4.2",
+      "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-17.4.2.tgz",
+      "integrity": "sha512-nI4U3TottKAcAD9LLud4Cb7b2QztQMUEfHbvhTH09bqXTxnSie8WnjPALV/WMCrJZ6UV/qHJ6L03OqO3LcdYZw==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=12"
+      },
+      "funding": {
+        "url": "https://dotenvx.com"
+      }
+    },
     "node_modules/electron-to-chromium": {
       "version": "1.5.328",
       "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.5.328.tgz",
@@ -2124,6 +2162,32 @@
       "integrity": "sha512-RbJ5/jmFcNNCcDV5o9eTnBLJ/HszWV0P73bc+Ff4nS/rJj+YaS6IGyiOL0VoBYX+l1Wrl3k63h/KrH+nhJ0XvQ==",
       "license": "ISC"
     },
+    "node_modules/graphql": {
+      "version": "17.0.2",
+      "resolved": "https://registry.npmjs.org/graphql/-/graphql-17.0.2.tgz",
+      "integrity": "sha512-FRWbddMxfkjiB7z+aQDWIR+E34xo9I8c9mtK2RPv8PmMzKRvrdsreHL/Ui/TmwHJfhHChEtsFPyMHKI+xuarQQ==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^22.0.0 || ^24.0.0 || ^25.0.0 || >=26.0.0"
+      }
+    },
+    "node_modules/graphql-tag": {
+      "version": "2.12.7",
+      "resolved": "https://registry.npmjs.org/graphql-tag/-/graphql-tag-2.12.7.tgz",
+      "integrity": "sha512-xnE/NFzy+0eIesvAsREJZ284zTl/wYuBAvpsFSDhRGRdRHdnE90M21Q3xAWyYInb0J756c6x0pIQ62+vtvOs1Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "^2.1.0"
+      },
+      "engines": {
+        "node": ">=10"
+      },
+      "peerDependencies": {
+        "graphql": "^0.9.0 || ^0.10.0 || ^0.11.0 || ^0.12.0 || ^0.13.0 || ^14.0.0 || ^15.0.0 || ^16.0.0 || ^17.0.0"
+      }
+    },
     "node_modules/iconv-lite": {
       "version": "0.6.3",
       "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.6.3.tgz",
@@ -2824,6 +2888,13 @@
       "integrity": "sha512-+FbBPE1o9QAYvviau/qC5SE3caw21q3xkvWKBtja5vgqOWIHHJ3ioaq1VPfn/Szqctz2bU/oYeKd9/z5BL+PVg==",
       "license": "MIT"
     },
+    "node_modules/tslib": {
+      "version": "2.8.1",
+      "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.8.1.tgz",
+      "integrity": "sha512-oJFu94HQb+KVduSUQL7wnpmqnfmLsOA/nAh6b6EH0wCEoK0/mPeXU6c3wKDV83MkOuHPRHtSXKKU99IBazS/2w==",
+      "devOptional": true,
+      "license": "0BSD"
+    },
     "node_modules/update-browserslist-db": {
       "version": "1.2.3",
       "resolved": "https://registry.npmjs.org/update-browserslist-db/-/update-browserslist-db-1.2.3.tgz",
@@ -2942,6 +3013,16 @@
       "integrity": "sha512-a4UGQaWPH59mOXUYnAG2ewncQS4i4F43Tv3JoAM+s2VDAmS9NsK8GpDMLrCHPksFT7h3K6TOoUNn2pb7RoXx4g==",
       "dev": true,
       "license": "ISC"
+    },
+    "node_modules/zod": {
+      "version": "4.4.3",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-4.4.3.tgz",
+      "integrity": "sha512-ytENFjIJFl2UwYglde2jchW2Hwm4GJFLDiSXWdTrJQBIN9Fcyp7n4DhxJEiWNAJMV1/BqWfW/kkg71UDcHJyTQ==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
     }
   }
 }
diff --git a/package.json b/package.json
index 2734074..b0b8b89 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,8 @@
   "scripts": {
     "dev": "vite",
     "build": "vite build",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "validate-api": "node scripts/validate-api.js"
   },
   "dependencies": {
     "@tailwindcss/vite": "^4.3.0",
@@ -19,7 +20,11 @@
     "tailwindcss": "^4.3.0"
   },
   "devDependencies": {
+    "@octokit/graphql-schema": "^15.26.1",
     "@vitejs/plugin-react": "^4.3.1",
-    "vite": "^5.4.6"
+    "dotenv": "^17.4.2",
+    "graphql": "^17.0.2",
+    "vite": "^5.4.6",
+    "zod": "^4.4.3"
   }
 }
diff --git a/scripts/validate-api.js b/scripts/validate-api.js
new file mode 100644
index 0000000..1462688
--- /dev/null
+++ b/scripts/validate-api.js
@@ -0,0 +1,498 @@
+import dotenv from 'dotenv';
+import { z } from 'zod';
+import { validate as validateGraphQL } from '@octokit/graphql-schema';
+import * as queries from '../src/services/queries.js';
+
+dotenv.config();
+
+const token = process.env.GITHUB_TOKEN || process.env.GITHUB_PAT || '';
+
+// ANSI Colors for output formatting
+const colors = {
+  reset: '\x1b[0m',
+  red: '\x1b[31m',
+  green: '\x1b[32m',
+  yellow: '\x1b[33m',
+  blue: '\x1b[34m',
+  cyan: '\x1b[36m',
+  bold: '\x1b[1m'
+};
+
+// ==========================================
+// Zod Schemas for GitHub REST API Responses
+// ==========================================
+
+export const OrganizationSchema = z.object({
+  login: z.string(),
+  name: z.string().nullable().optional(),
+  public_repos: z.number(),
+  avatar_url: z.url(),
+  description: z.string().nullable().optional(),
+});
+
+export const RepositorySchema = z.object({
+  name: z.string(),
+  pushed_at: z.string(), // ISO date string or similar timestamp representation
+  open_issues_count: z.number(),
+  stargazers_count: z.number(),
+  forks_count: z.number(),
+  watchers_count: z.number(),
+  language: z.string().nullable().optional(),
+  license: z.object({
+    key: z.string(),
+    name: z.string(),
+    spdx_id: z.string().nullable().optional(),
+    url: z.url().nullable().optional(),
+    node_id: z.string().optional(),
+  }).nullable().optional(),
+  archived: z.boolean(),
+  fork: z.boolean(),
+});
+
+export const ContributorSchema = z.object({
+  login: z.string(),
+  avatar_url: z.url(),
+  contributions: z.number(),
+});
+
+export const IssueSchema = z.object({
+  title: z.string(),
+  number: z.number(),
+  user: z.object({
+    login: z.string(),
+  }).nullable().optional(),
+  created_at: z.string(),
+  updated_at: z.string(),
+  html_url: z.url().optional(),
+  pull_request: z.object({
+    url: z.url().optional(),
+    html_url: z.url().optional(),
+  }).nullable().optional(),
+  state: z.string(),
+});
+
+export const RateLimitSchema = z.object({
+  limit: z.number(),
+  remaining: z.number(),
+  reset: z.number(),
+  used: z.number(),
+});
+
+// ==========================================
+// Zod Schemas for GitHub GraphQL Responses
+// ==========================================
+
+export const GraphQLOrgDetailsSchema = z.object({
+  organization: z.object({
+    login: z.string(),
+    name: z.string().nullable().optional(),
+    description: z.string().nullable().optional(),
+    avatarUrl: z.string().url(),
+    repositories: z.object({
+      totalCount: z.number(),
+    }),
+  }).nullable(),
+});
+
+export const GraphQLOrgReposSchema = z.object({
+  organization: z.object({
+    repositories: z.object({
+      pageInfo: z.object({
+        hasNextPage: z.boolean(),
+        endCursor: z.string().nullable().optional(),
+      }),
+      nodes: z.array(z.object({
+        name: z.string(),
+        pushedAt: z.string(),
+        stargazerCount: z.number(),
+        forkCount: z.number(),
+        watchers: z.object({
+          totalCount: z.number(),
+        }),
+        primaryLanguage: z.object({
+          name: z.string(),
+        }).nullable().optional(),
+        licenseInfo: z.object({
+          key: z.string(),
+          name: z.string(),
+        }).nullable().optional(),
+        isArchived: z.boolean(),
+        isFork: z.boolean(),
+      })),
+    }),
+  }).nullable(),
+});
+
+export const GraphQLRepoIssuesSchema = z.object({
+  repository: z.object({
+    issues: z.object({
+      pageInfo: z.object({
+        hasNextPage: z.boolean(),
+        endCursor: z.string().nullable().optional(),
+      }),
+      nodes: z.array(z.object({
+        title: z.string(),
+        number: z.number(),
+        createdAt: z.string(),
+        updatedAt: z.string(),
+        state: z.string(),
+        url: z.string().url(),
+        author: z.object({
+          login: z.string(),
+        }).nullable().optional(),
+      })),
+    }),
+  }).nullable(),
+});
+
+// ==========================================
+// Static Mock Data for Local Validation Tests
+// ==========================================
+
+const mockFixtures = {
+  organization: {
+    login: 'AOSSIE-Org',
+    name: 'AOSSIE',
+    public_repos: 12,
+    avatar_url: 'https://avatars.githubusercontent.com/u/12345',
+    description: 'An open source organization'
+  },
+  repository: {
+    name: 'OrgExplorer',
+    pushed_at: '2026-07-05T12:00:00Z',
+    open_issues_count: 5,
+    stargazers_count: 42,
+    forks_count: 10,
+    watchers_count: 42,
+    language: 'JavaScript',
+    license: {
+      key: 'gpl-3.0',
+      name: 'GNU General Public License v3.0'
+    },
+    archived: false,
+    fork: false
+  },
+  contributor: {
+    login: 'kpj2006',
+    avatar_url: 'https://avatars.githubusercontent.com/u/54321',
+    contributions: 150
+  },
+  issue: {
+    title: 'Fix sidebar responsiveness',
+    number: 101,
+    user: {
+      login: 'aossie_dev'
+    },
+    created_at: '2026-07-01T10:00:00Z',
+    updated_at: '2026-07-04T15:00:00Z',
+    html_url: 'https://github.com/AOSSIE-Org/OrgExplorer/issues/101',
+    pull_request: null,
+    state: 'open'
+  },
+  rateLimit: {
+    limit: 5000,
+    remaining: 4999,
+    reset: Math.floor(Date.now() / 1000) + 3600,
+    used: 1
+  }
+};
+
+// ==========================================
+// Helper Functions
+// ==========================================
+
+async function fetchREST(url) {
+  const headers = { Accept: 'application/vnd.github.v3+json' };
+  if (token) {
+    headers.Authorization = `token ${token}`;
+  }
+  const res = await fetch(url, { headers });
+  if (res.status === 403) {
+    const error = new Error(`REST Rate Limit or Forbidden for ${url}. Consider adding a GITHUB_TOKEN.`);
+    error.status = 403;
+    throw error;
+  }
+  if (!res.ok) {
+    throw new Error(`REST Fetch failed for ${url}: ${res.status} ${res.statusText}`);
+  }
+  return res.json();
+}
+
+async function fetchGraphQL(query, variables = {}) {
+  const res = await fetch('https://api.github.com/graphql', {
+    method: 'POST',
+    headers: {
+      Authorization: `bearer ${token}`,
+      'Content-Type': 'application/json',
+      'User-Agent': 'OrgExplorer-Schema-Validator'
+    },
+    body: JSON.stringify({ query, variables }),
+  });
+  if (!res.ok) {
+    throw new Error(`GraphQL Fetch failed: ${res.status} ${res.statusText}`);
+  }
+  const json = await res.json();
+  if (json.errors && json.errors.length > 0) {
+    const errorMsg = json.errors.map(e => e.message).join('; ');
+    throw new Error(`GraphQL Error: ${errorMsg}`);
+  }
+  return json.data;
+}
+
+function handleZodError(error, contextName) {
+  console.error(`\n${colors.red}${colors.bold}❌ Validation failed in context: ${contextName}${colors.reset}`);
+  const issues = error.issues || error.errors || [];
+  issues.forEach(err => {
+    const fieldPath = err.path.join('.');
+    console.error(`  - Field: ${colors.cyan}${fieldPath}${colors.reset}`);
+    console.error(`    Error: ${colors.yellow}${err.message}${colors.reset} (code: ${err.code})`);
+  });
+}
+
+async function validateLiveRESTCollection({
+  url,
+  schema,
+  startMsg,
+  successMsg,
+  skipMsg,
+  errorMsg,
+  isArray = false,
+  getZodContext,
+  transform = (data) => data,
+  collectionTypeLabel = ''
+}) {
+  try {
+    console.log(`  ${startMsg}`);
+    const data = await fetchREST(url);
+    if (isArray) {
+      if (Array.isArray(data)) {
+        let valid = true;
+        for (const item of data) {
+          const parseResult = schema.safeParse(item);
+          if (!parseResult.success) {
+            failed = true;
+            valid = false;
+            handleZodError(parseResult.error, getZodContext(item));
+          }
+        }
+        if (valid) {
+          const formattedSuccess = successMsg.replace('{count}', data.length);
+          console.log(`  ${colors.green}✓ ${formattedSuccess}${colors.reset}`);
+        }
+      } else {
+        failed = true;
+        console.error(`  ${colors.red}❌ Expected array of ${collectionTypeLabel}, got: ${typeof data}${colors.reset}`);
+      }
+    } else {
+      const targetData = transform(data);
+      const parseResult = schema.safeParse(targetData);
+      if (!parseResult.success) {
+        failed = true;
+        handleZodError(parseResult.error, getZodContext(data));
+      } else {
+        console.log(`  ${colors.green}✓ ${successMsg}${colors.reset}`);
+      }
+    }
+  } catch (err) {
+    if (!token && err.status === 403) {
+      console.log(`  ${colors.yellow}⚠ ${skipMsg}${colors.reset}`);
+    } else {
+      failed = true;
+      console.error(`  ${colors.red}❌ ${errorMsg}: ${err.message}${colors.reset}`);
+    }
+  }
+}
+
+// ==========================================
+// Main Runner
+// ==========================================
+
+let failed = false;
+
+async function main() {
+  failed = false;
+
+  console.log(`\n${colors.blue}${colors.bold}=== OrgExplorer Data Schema & API Validation ===${colors.reset}\n`);
+
+  if (token) {
+    console.log(`${colors.green}🔑 GitHub token found. Running in authenticated mode (full integration checks).${colors.reset}`);
+  } else {
+    console.log(`${colors.yellow}⚠️ No GitHub token found. Running in unauthenticated mode (live GraphQL skipped, live REST may hit rate limits).${colors.reset}`);
+  }
+
+  // ------------------------------------------
+  // 1. Static GraphQL Query Syntax Validation
+  // ------------------------------------------
+  console.log(`\n${colors.cyan}${colors.bold}Step 1: Statically validating GraphQL query syntax...${colors.reset}`);
+
+  for (const [name, query] of Object.entries(queries)) {
+    console.log(`  Validating ${colors.bold}${name}${colors.reset}...`);
+    const errors = validateGraphQL(query);
+    if (errors.length > 0) {
+      failed = true;
+      console.error(`  ${colors.red}❌ ${name} is invalid:${colors.reset}`);
+      errors.forEach(err => console.error(`    - ${err.message}`));
+    } else {
+      console.log(`  ${colors.green}✓ ${name} is syntactically valid against GitHub schema.${colors.reset}`);
+    }
+  }
+
+  // ------------------------------------------
+  // 2. Static Schema Validation (Mock Fixtures)
+  // ------------------------------------------
+  console.log(`\n${colors.cyan}${colors.bold}Step 2: Statically validating schemas with mock fixtures...${colors.reset}`);
+
+  const staticTests = [
+    { name: 'OrganizationSchema', schema: OrganizationSchema, data: mockFixtures.organization },
+    { name: 'RepositorySchema', schema: RepositorySchema, data: mockFixtures.repository },
+    { name: 'ContributorSchema', schema: ContributorSchema, data: mockFixtures.contributor },
+    { name: 'IssueSchema', schema: IssueSchema, data: mockFixtures.issue },
+    { name: 'RateLimitSchema', schema: RateLimitSchema, data: mockFixtures.rateLimit }
+  ];
+
+  for (const test of staticTests) {
+    const result = test.schema.safeParse(test.data);
+    if (!result.success) {
+      failed = true;
+      handleZodError(result.error, `Static Mock - ${test.name}`);
+    } else {
+      console.log(`  ${colors.green}✓ ${test.name} correctly parsed mock data.${colors.reset}`);
+    }
+  }
+
+  // ------------------------------------------
+  // 3. Live API Schema Validation (Integration)
+  // ------------------------------------------
+  console.log(`\n${colors.cyan}${colors.bold}Step 3: Validating live GitHub API responses (detecting breaking changes)...${colors.reset}`);
+
+  // Test target info
+  const testOrg = 'AOSSIE-Org';
+  const testRepo = 'OrgExplorer';
+
+  // Live REST API checks
+  await validateLiveRESTCollection({
+    url: `https://api.github.com/orgs/${testOrg}`,
+    schema: OrganizationSchema,
+    startMsg: `Fetching live Org details for ${colors.bold}${testOrg}${colors.reset}...`,
+    successMsg: `Live REST organization schema matches expectations.`,
+    skipMsg: `Skipped live Org REST fetch due to rate limiting (no token provided).`,
+    errorMsg: `Error fetching live Org REST`,
+    isArray: false,
+    getZodContext: () => `Live REST - Organization: ${testOrg}`
+  });
+
+  await validateLiveRESTCollection({
+    url: `https://api.github.com/orgs/${testOrg}/repos?per_page=5`,
+    schema: RepositorySchema,
+    startMsg: `Fetching live repositories for ${colors.bold}${testOrg}${colors.reset}...`,
+    successMsg: `Live REST repositories schema matches expectations (checked {count} repos).`,
+    skipMsg: `Skipped live repos REST fetch due to rate limiting.`,
+    errorMsg: `Error fetching live Repos REST`,
+    isArray: true,
+    collectionTypeLabel: 'repos',
+    getZodContext: (repo) => `Live REST - Repository: ${repo.name}`
+  });
+
+  await validateLiveRESTCollection({
+    url: `https://api.github.com/repos/${testOrg}/${testRepo}/contributors?per_page=5`,
+    schema: ContributorSchema,
+    startMsg: `Fetching live contributors for ${colors.bold}${testOrg}/${testRepo}${colors.reset}...`,
+    successMsg: `Live REST contributors schema matches expectations (checked {count} contribs).`,
+    skipMsg: `Skipped live contributors REST fetch due to rate limiting.`,
+    errorMsg: `Error fetching live Contributors REST`,
+    isArray: true,
+    collectionTypeLabel: 'contributors',
+    getZodContext: (c) => `Live REST - Contributor: ${c.login}`
+  });
+
+  await validateLiveRESTCollection({
+    url: `https://api.github.com/repos/${testOrg}/${testRepo}/issues?per_page=5&state=all`,
+    schema: IssueSchema,
+    startMsg: `Fetching live issues for ${colors.bold}${testOrg}/${testRepo}${colors.reset}...`,
+    successMsg: `Live REST issues schema matches expectations (checked {count} issues).`,
+    skipMsg: `Skipped live issues REST fetch due to rate limiting.`,
+    errorMsg: `Error fetching live Issues REST`,
+    isArray: true,
+    collectionTypeLabel: 'issues',
+    getZodContext: (issue) => `Live REST - Issue: #${issue.number}`
+  });
+
+  await validateLiveRESTCollection({
+    url: `https://api.github.com/rate_limit`,
+    schema: RateLimitSchema,
+    startMsg: `Fetching live rate limit status...`,
+    successMsg: `Live REST rate limit schema matches expectations.`,
+    skipMsg: `Skipped live rate limit REST fetch due to rate limiting.`,
+    errorMsg: `Error fetching live RateLimit REST`,
+    isArray: false,
+    transform: (liveRate) => liveRate.rate,
+    getZodContext: () => `Live REST - RateLimit`
+  });
+
+  // Live GraphQL API checks
+  if (token) {
+    try {
+      console.log(`  Running live GraphQL query: ${colors.bold}GET_ORG_DETAILS${colors.reset} for ${testOrg}...`);
+      const res = await fetchGraphQL(queries.GET_ORG_DETAILS, { login: testOrg });
+      const parseResult = GraphQLOrgDetailsSchema.safeParse(res);
+      if (!parseResult.success) {
+        failed = true;
+        handleZodError(parseResult.error, 'Live GraphQL - GET_ORG_DETAILS');
+      } else {
+        console.log(`  ${colors.green}✓ Live GraphQL GET_ORG_DETAILS matches expectations.${colors.reset}`);
+      }
+    } catch (err) {
+      failed = true;
+      console.error(`  ${colors.red}❌ Error in live GraphQL GET_ORG_DETAILS: ${err.message}${colors.reset}`);
+    }
+
+    try {
+      console.log(`  Running live GraphQL query: ${colors.bold}GET_ORG_REPOS${colors.reset} for ${testOrg}...`);
+      const res = await fetchGraphQL(queries.GET_ORG_REPOS, { login: testOrg, first: 3 });
+      const parseResult = GraphQLOrgReposSchema.safeParse(res);
+      if (!parseResult.success) {
+        failed = true;
+        handleZodError(parseResult.error, 'Live GraphQL - GET_ORG_REPOS');
+      } else {
+        console.log(`  ${colors.green}✓ Live GraphQL GET_ORG_REPOS matches expectations.${colors.reset}`);
+      }
+    } catch (err) {
+      failed = true;
+      console.error(`  ${colors.red}❌ Error in live GraphQL GET_ORG_REPOS: ${err.message}${colors.reset}`);
+    }
+
+    try {
+      console.log(`  Running live GraphQL query: ${colors.bold}GET_REPO_ISSUES${colors.reset} for ${testOrg}/${testRepo}...`);
+      const res = await fetchGraphQL(queries.GET_REPO_ISSUES, { owner: testOrg, name: testRepo, first: 3 });
+      const parseResult = GraphQLRepoIssuesSchema.safeParse(res);
+      if (!parseResult.success) {
+        failed = true;
+        handleZodError(parseResult.error, 'Live GraphQL - GET_REPO_ISSUES');
+      } else {
+        console.log(`  ${colors.green}✓ Live GraphQL GET_REPO_ISSUES matches expectations.${colors.reset}`);
+      }
+    } catch (err) {
+      failed = true;
+      console.error(`  ${colors.red}❌ Error in live GraphQL GET_REPO_ISSUES: ${err.message}${colors.reset}`);
+    }
+  } else {
+    console.log(`\n${colors.yellow}⚠️ Live GraphQL validation skipped: GITHUB_TOKEN or GITHUB_PAT not set.${colors.reset}`);
+  }
+
+  // ------------------------------------------
+  // Summary and Exit Code
+  // ------------------------------------------
+  console.log(`\n${colors.bold}=== Validation Summary ===${colors.reset}`);
+  if (failed) {
+    console.error(`${colors.red}${colors.bold}❌ Schema / API Validation FAILED! Check error outputs above.${colors.reset}\n`);
+    process.exit(1);
+  } else {
+    console.log(`${colors.green}${colors.bold}✓ All GraphQL query syntax and API schemas validated successfully!${colors.reset}\n`);
+    process.exit(0);
+  }
+}
+
+main().catch(err => {
+  console.error(`${colors.red}Fatal Error: ${err.message}${colors.reset}`);
+  process.exit(1);
+});
diff --git a/src/services/queries.js b/src/services/queries.js
new file mode 100644
index 0000000..73c88bc
--- /dev/null
+++ b/src/services/queries.js
@@ -0,0 +1,70 @@
+// Reusable GitHub GraphQL query strings for OrgExplorer API validation
+
+export const GET_ORG_DETAILS = `
+  query GetOrgDetails($login: String!) {
+    organization(login: $login) {
+      login
+      name
+      description
+      avatarUrl
+      repositories {
+        totalCount
+      }
+    }
+  }
+`;
+
+export const GET_ORG_REPOS = `
+  query GetOrgRepos($login: String!, $first: Int!, $after: String) {
+    organization(login: $login) {
+      repositories(first: $first, after: $after, orderBy: {field: PUSHED_AT, direction: DESC}) {
+        pageInfo {
+          hasNextPage
+          endCursor
+        }
+        nodes {
+          name
+          pushedAt
+          stargazerCount
+          forkCount
+          watchers {
+            totalCount
+          }
+          primaryLanguage {
+            name
+          }
+          licenseInfo {
+            key
+            name
+          }
+          isArchived
+          isFork
+        }
+      }
+    }
+  }
+`;
+
+export const GET_REPO_ISSUES = `
+  query GetRepoIssues($owner: String!, $name: String!, $first: Int!, $after: String) {
+    repository(owner: $owner, name: $name) {
+      issues(first: $first, after: $after, states: [OPEN, CLOSED]) {
+        pageInfo {
+          hasNextPage
+          endCursor
+        }
+        nodes {
+          title
+          number
+          createdAt
+          updatedAt
+          state
+          url
+          author {
+            login
+          }
+        }
+      }
+    }
+  }
+`;