Create mcpcat.md

Upgrade package to version 3.2.0 and address code quality improvements based on review feedback

.github/PULL_REQUEST_TEMPLATE/mcpcat.md

@@ -0,0 +1,44 @@
+# Add optional MCPcat analytics scaffolding (`--with-mcpcat`) to generated MCP servers
+
+> **TL;DR**: This PR adds an **opt-in** flag to scaffold privacy-safe analytics wiring for MCPcat in projects generated by `openapi-mcp-generator`.
+
+## Summary
+This PR introduces a `--with-mcpcat` CLI flag that scaffolds:
+- A tiny analytics shim to emit initialize/tool-call events.
+- A default **local redaction** helper to scrub sensitive data before export.
+- Minimal config via environment variables.
+No behavior changes unless the flag and env vars are set.
+
+## Motivation
+- Make freshly generated MCP servers **observable in minutes**.
+- Encourage **privacy-by-default** analytics patterns.
+- Reduce copy/paste wiring; standardize event shape (operationId, path, duration, status).
+
+## Changes
+### CLI
+- `generate` accepts `--with-mcpcat` (default: off).
+
+### Template files (added conditionally)
+- `src/analytics/mcpcat.ts` – lazy import + safe no-op if SDK absent.
+- `src/analytics/redact.ts` – OpenAPI-aware heuristics (e.g., `*token*`, `password`, `apiKey`, `authorization`, `email`).
+- `src/analytics/config.ts` – reads env:
+  - `MCPCAT_ENABLED=true|false` (default `false`)
+  - `MCPCAT_PROJECT_ID=<id>`
+  - `MCPCAT_ENDPOINT=<optional override>`
+  - `MCPCAT_SAMPLE_RATE=1.0` (0–1)
+
+### Server wiring
+- Hooks server `.initialize` and each tool invocation to record:
+  - `operationId`, HTTP `method`, `path`
+  - redacted `args`
+  - `outcome` (`ok`/`error`) + truncated error message
+  - `duration_ms`
+
+### Docs
+- Adds a “Enable analytics (MCPcat)” section to generated README with privacy notes and quickstart.
+
+## Implementation Notes
+- **Compile-time optional**: no imports unless flag is used.
+- **Runtime safe**: try/catch around SDK import → graceful no-op if not installed.
+- **Transport-agnostic**: compatible with stdio, SSE/web, and StreamableHTTP templates.
+- **Edge-friendly**: avoids Node-only APIs in scaffolding to support edge runtimes (e.g., Workers).

CHANGELOG.md

@@ -5,6 +5,41 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.2.0] - 2025-08-24
+
+### Added
+
+- Endpoint filtering using `x-mcp` OpenAPI extension to control which operations are exposed as MCP tools
+- CLI option `--default-include` to change default behavior for endpoint inclusion
+- Precedence rules for `x-mcp` extension (operation > path > root level)
+- Enhanced programmatic API with `defaultInclude` option in `getToolsFromOpenApi`
+
+### Changed
+
+- Improved documentation with examples for endpoint filtering and OpenAPI extensions.
+- Version bump to next minor release
+- Updated package version to reflect accumulated features and improvements
+
+## [3.1.4] - 2025-06-18
+
+### Chores
+
+- Updated the application version to 3.1.4 and ensured the CLI displays the version dynamically.
+
+### Style
+
+- Improved code formatting for better readability.
+
+### Bug Fixes
+
+- Tool names now retain their original casing during extraction.
+
+## [3.1.3] - 2025-06-12
+
+### Fixed
+
+- Cannot find the package after building and the problem during the building.
+
 ## [3.1.2] - 2025-06-08
 
 ### Fixed

PROGRAMMATIC_API.md

@@ -64,6 +64,20 @@ for (const tool of filteredTools) {
 }
 ```
 
+you can also provide a `OpenAPIV3.Document` to the parser:
+
+```typescript
+import { parser } from '@readme/openapi-parser';
+
+const api = await parser('https://petstore3.swagger.io/api/v3/openapi.json', {
+  dereference: {
+    circular: true,
+  },
+});
+
+const tools = await getToolsFromOpenApi(api);
+```
+
 ## Tool Definition Structure
 
 Each tool definition (`McpToolDefinition`) has the following properties:

README.md

@@ -49,7 +49,7 @@ openapi-mcp-generator --input path/to/openapi.json --output path/to/output/dir -
 ### CLI Options
 
 | Option              | Alias | Description                                                                                                                                    | Default                           |
-| ------------------ | ----- | ------------------------------------------------------------------------------ | --------------------------------- |
+| ------------------- | ----- | ---------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------- |
 | `--input`           | `-i`  | Path or URL to OpenAPI specification (YAML or JSON)                                                                                            | **Required**                      |
 | `--output`          | `-o`  | Directory to output the generated MCP project                                                                                                  | **Required**                      |
 | `--server-name`     | `-n`  | Name of the MCP server (`package.json:name`)                                                                                                   | OpenAPI title or `mcp-api-server` |
@@ -57,6 +57,7 @@ openapi-mcp-generator --input path/to/openapi.json --output path/to/output/dir -
 | `--base-url`        | `-b`  | Base URL for API requests. Required if OpenAPI `servers` missing or ambiguous.                                                                 | Auto-detected if possible         |
 | `--transport`       | `-t`  | Transport mode: `"stdio"` (default), `"web"`, or `"streamable-http"`                                                                           | `"stdio"`                         |
 | `--port`            | `-p`  | Port for web-based transports                                                                                                                  | `3000`                            |
+| `--default-include` |       | Default behavior for x-mcp filtering. Accepts `true` or `false` (case-insensitive). `true` = include by default, `false` = exclude by default. | `true`                            |
 | `--force`           |       | Overwrite existing files in the output directory without confirmation                                                                          | `false`                           |
 
 ## 📦 Programmatic API
@@ -167,6 +168,38 @@ Configure auth credentials in your environment:
 
 ---
 
+## 🔎 Filtering Endpoints with OpenAPI Extensions
+
+You can control which operations are exposed as MCP tools using a vendor extension flag `x-mcp`. This extension is supported at the root, path, and operation levels. By default, endpoints are included unless explicitly excluded.
+
+- Extension: `x-mcp: true | false`
+- Default: `true` (include by default)
+- Precedence: operation > path > root (first non-undefined wins)
+- CLI option: `--default-include false` to change default to exclude by default
+
+Examples:
+
+```yaml
+# Optional root-level default
+x-mcp: true
+
+paths:
+  /pets:
+    x-mcp: false # exclude all ops under /pets
+    get:
+      x-mcp: true # include this operation anyway
+
+  /users/{id}:
+    get:
+      # no x-mcp -> included by default
+```
+
+This uses standard OpenAPI extensions (x-… fields). See the [OpenAPI Extensions guide](https://swagger.io/docs/specification/v3_0/openapi-extensions/) for details.
+
+Note: `x-mcp` must be a boolean or the strings `"true"`/`"false"` (case-insensitive). Other values are ignored in favor of higher-precedence or default behavior.
+
+---
+
 ## ▶️ Running the Generated Server
 
 ```bash

package.json

@@ -1,6 +1,6 @@
 {
   "name": "openapi-mcp-generator",
-  "version": "3.1.4",
+  "version": "3.2.0",
   "description": "Generates MCP server code from OpenAPI specifications",
   "license": "MIT",
   "author": "Harsha",
@@ -25,7 +25,7 @@
     "format.check": "prettier --check .",
     "format.write": "prettier --write .",
     "typecheck": "tsc --noEmit",
-    "build": "tsc && chmod 755 dist/index.js && chmod 755 bin/openapi-mcp-generator.js",
+    "build": "tsc && chmod 755 dist/index.js bin/openapi-mcp-generator.js",
     "version:patch": "npm version patch",
     "version:minor": "npm version minor",
     "version:major": "npm version major"
@@ -53,16 +53,16 @@
     "openapi-types": "^12.1.3"
   },
   "devDependencies": {
-    "@types/node": "^22.15.2",
+    "@types/node": "^22.17.2",
-    "@typescript-eslint/eslint-plugin": "^8.31.0",
+    "@typescript-eslint/eslint-plugin": "^8.39.1",
-    "@typescript-eslint/parser": "^8.31.0",
+    "@typescript-eslint/parser": "^8.39.1",
-    "eslint": "^9.25.1",
+    "eslint": "^9.33.0",
-    "prettier": "^3.5.3",
+    "prettier": "^3.6.2",
     "rimraf": "^6.0.1",
-    "typescript": "^5.8.3"
+    "typescript": "^5.9.2"
   },
   "peerDependencies": {
-    "@modelcontextprotocol/sdk": "^1.10.0",
+    "@modelcontextprotocol/sdk": "^1.10.2",
     "json-schema-to-zod": "^2.6.1",
     "zod": "^3.24.3"
   }

src/api.ts

@@ -24,6 +24,13 @@ export interface GetToolsOptions {
 
   /** Optional filter function to exclude tools based on custom criteria */
   filterFn?: (tool: McpToolDefinition) => boolean;
+
+  /** Default behavior for x-mcp filtering (default: true = include by default) */
+  defaultInclude?: boolean;
+}
+
+function isOpenApiDocument(spec: string | OpenAPIV3.Document): spec is OpenAPIV3.Document {
+  return typeof spec === 'object' && spec !== null && 'openapi' in spec;
 }
 
 /**
@@ -34,17 +41,19 @@ export interface GetToolsOptions {
  * @returns Promise that resolves to an array of tool definitions
  */
 export async function getToolsFromOpenApi(
-  specPathOrUrl: string,
+  specPathOrUrl: string | OpenAPIV3.Document,
   options: GetToolsOptions = {}
 ): Promise<McpToolDefinition[]> {
   try {
     // Parse the OpenAPI spec
-    const api = options.dereference
+    const api = isOpenApiDocument(specPathOrUrl)
+      ? specPathOrUrl
+      : options.dereference
         ? ((await SwaggerParser.dereference(specPathOrUrl)) as OpenAPIV3.Document)
         : ((await SwaggerParser.parse(specPathOrUrl)) as OpenAPIV3.Document);
 
     // Extract tools from the API
-    const allTools = extractToolsFromApi(api);
+    const allTools = extractToolsFromApi(api, options.defaultInclude ?? true);
 
     // Add base URL to each tool
     const baseUrl = determineBaseUrl(api, options.baseUrl);
@@ -71,7 +80,8 @@ export async function getToolsFromOpenApi(
   } catch (error) {
     // Provide more context for the error
     if (error instanceof Error) {
-      throw new Error(`Failed to extract tools from OpenAPI: ${error.message}`);
+      // Preserve original stack/context
+      throw new Error(`Failed to extract tools from OpenAPI: ${error.message}`, { cause: error });
     }
     throw error;
   }

src/generator/server-code.ts

@@ -25,7 +25,7 @@ export function generateMcpServerCode(
   serverVersion: string
 ): string {
   // Extract tools from API
-  const tools = extractToolsFromApi(api);
+  const tools = extractToolsFromApi(api, options.defaultInclude ?? true);
 
   // Determine base URL
   const determinedBaseUrl = determineBaseUrl(api, options.baseUrl);

src/index.ts

@@ -30,6 +30,7 @@ import {
 
 // Import types
 import { CliOptions, TransportType } from './types/index.js';
+import { normalizeBoolean } from './utils/helpers.js';
 import pkg from '../package.json' with { type: 'json' };
 
 // Export programmatic API
@@ -72,6 +73,19 @@ program
     'Port for web or streamable-http transport (default: 3000)',
     (val) => parseInt(val, 10)
   )
+  .option(
+    '--default-include <boolean>',
+    'Default behavior for x-mcp filtering (true|false, case-insensitive). Default: true (include by default), false = exclude by default',
+    (val) => {
+      const parsed = normalizeBoolean(val);
+      if (typeof parsed === 'boolean') return parsed;
+      console.warn(
+        `Invalid value for --default-include: "${val}". Expected true/false (case-insensitive). Using default: true.`
+      );
+      return true;
+    },
+    true
+  )
   .option('--force', 'Overwrite existing files without prompting')
   .version(pkg.version) // Match package.json version
   .action((options) => {

src/parser/extract-tools.ts

@@ -5,6 +5,7 @@ import { OpenAPIV3 } from 'openapi-types';
 import type { JSONSchema7, JSONSchema7TypeName } from 'json-schema';
 import { generateOperationId } from '../utils/code-gen.js';
 import { McpToolDefinition } from '../types/index.js';
+import { shouldIncludeOperationForMcp } from '../utils/helpers.js';
 
 /**
  * Extracts tool definitions from an OpenAPI document
@@ -12,7 +13,10 @@ import { McpToolDefinition } from '../types/index.js';
  * @param api OpenAPI document
  * @returns Array of MCP tool definitions
  */
-export function extractToolsFromApi(api: OpenAPIV3.Document): McpToolDefinition[] {
+export function extractToolsFromApi(
+  api: OpenAPIV3.Document,
+  defaultInclude: boolean = true
+): McpToolDefinition[] {
   const tools: McpToolDefinition[] = [];
   const usedNames = new Set<string>();
   const globalSecurity = api.security || [];
@@ -26,6 +30,37 @@ export function extractToolsFromApi(api: OpenAPIV3.Document): McpToolDefinition[
       const operation = pathItem[method];
       if (!operation) continue;
 
+      // Apply x-mcp filtering, precedence: operation > path > root
+      try {
+        if (
+          !shouldIncludeOperationForMcp(
+            api,
+            pathItem as OpenAPIV3.PathItemObject,
+            operation,
+            defaultInclude
+          )
+        ) {
+          continue;
+        }
+      } catch (error) {
+        const loc = operation.operationId || `${method} ${path}`;
+        const extVal =
+          (operation as any)['x-mcp'] ?? (pathItem as any)['x-mcp'] ?? (api as any)['x-mcp'];
+        let extPreview: string;
+        try {
+          extPreview = JSON.stringify(extVal);
+        } catch {
+          extPreview = String(extVal);
+        }
+        console.warn(
+          `Error evaluating x-mcp extension for operation ${loc} (x-mcp=${extPreview}):`,
+          error
+        );
+        if (!defaultInclude) {
+          continue;
+        }
+      }
+
       // Generate a unique name for the tool
       let baseName = operation.operationId || generateOperationId(method, path);
       if (!baseName) continue;

src/types/index.ts

@@ -29,6 +29,12 @@ export interface CliOptions {
   transport?: TransportType;
   /** Server port (for web and streamable-http transports) */
   port?: number;
+  /**
+   * Default behavior for x-mcp filtering.
+   * true (default) = include by default when x-mcp is missing or invalid;
+   * false = exclude by default unless x-mcp explicitly enables.
+   */
+  defaultInclude?: boolean;
 }
 
 /**

src/utils/helpers.ts

@@ -1,6 +1,7 @@
 /**
  * General helper utilities for OpenAPI to MCP generator
  */
+import { OpenAPIV3 } from 'openapi-types';
 
 /**
  * Safely stringify a JSON object with proper error handling
@@ -110,3 +111,63 @@ export function formatComment(str: string, maxLineLength: number = 80): string {
 
   return lines.join('\n * ');
 }
+
+/**
+ * Normalize a value to boolean if it looks like a boolean; otherwise undefined.
+ */
+export function normalizeBoolean(value: unknown): boolean | undefined {
+  if (typeof value === 'boolean') return value;
+  if (typeof value === 'string') {
+    const normalized = value.trim().toLowerCase();
+    if (['true', '1', 'yes', 'on'].includes(normalized)) return true;
+    if (['false', '0', 'no', 'off'].includes(normalized)) return false;
+    return undefined;
+  }
+  return undefined;
+}
+
+/**
+ * Determine if an operation should be included in MCP generation based on x-mcp.
+ * Precedence: operation > path > root; uses provided default when all undefined.
+ */
+export function shouldIncludeOperationForMcp(
+  api: OpenAPIV3.Document,
+  pathItem: OpenAPIV3.PathItemObject,
+  operation: OpenAPIV3.OperationObject,
+  defaultInclude: boolean = true
+): boolean {
+  const opRaw = (operation as any)['x-mcp'];
+  const opVal = normalizeBoolean(opRaw);
+  if (typeof opVal !== 'undefined') return opVal;
+  if (typeof opRaw !== 'undefined') {
+    console.warn(
+      `Invalid x-mcp value on operation '${operation.operationId ?? '[no operationId]'}':`,
+      opRaw,
+      `-> expected boolean or 'true'/'false'. Falling back to path/root/default.`
+    );
+  }
+
+  const pathRaw = (pathItem as any)['x-mcp'];
+  const pathVal = normalizeBoolean(pathRaw);
+  if (typeof pathVal !== 'undefined') return pathVal;
+  if (typeof pathRaw !== 'undefined') {
+    console.warn(
+      `Invalid x-mcp value on path item:`,
+      pathRaw,
+      `-> expected boolean or 'true'/'false'. Falling back to root/default.`
+    );
+  }
+
+  const rootRaw = (api as any)['x-mcp'];
+  const rootVal = normalizeBoolean(rootRaw);
+  if (typeof rootVal !== 'undefined') return rootVal;
+  if (typeof rootRaw !== 'undefined') {
+    console.warn(
+      `Invalid x-mcp value at API root:`,
+      rootRaw,
+      `-> expected boolean or 'true'/'false'. Falling back to defaultInclude=${defaultInclude}.`
+    );
+  }
+
+  return defaultInclude;
+}