# Implementation Summary: npm Package Tools
## Overview
This implementation adds comprehensive npm registry integration to the Ember MCP Server, allowing AI agents to fetch package information and help with dependency management.
## Files Added
### 1. `/lib/npm-service.js`
**Purpose**: Core service for interacting with npm registry API
**Key Features**:
- Fetches package data from registry.npmjs.org
- Gets latest versions and dist-tags (latest, beta, lts, etc.)
- Formats package information for display
- Compares versions for upgrade planning
- Comprehensive error handling
**Main Methods**:
- `getPackageInfo(packageName)` - Fetch raw package data
- `getLatestVersion(packageName)` - Get latest stable version
- `getDistTags(packageName)` - Get all distribution tags
- `formatPackageInfo(packageInfo)` - Format for display
- `getVersionComparison(packageName, currentVersion)` - Compare versions
### 2. `/test/npm-service.test.js`
**Purpose**: Comprehensive unit tests for npm service
**Test Coverage**:
- Real API calls to npm registry (could be mocked later)
- Error handling for non-existent packages
- Data formatting with various input scenarios
- Version comparison logic
- Edge cases (missing fields, null values)
**Results**: 12 tests, all passing
### 3. `/test/manual-npm-test.js`
**Purpose**: Manual testing script for quick verification
**Features**:
- Tests all major npm service functions
- Demonstrates error handling
- Can be run standalone for debugging
### 4. `/docs/npm-tools-examples.md`
**Purpose**: Comprehensive usage guide for the npm tools
**Contents**:
- Detailed examples of each tool
- Common use cases and patterns
- Integration with other MCP tools
- Best practices for agents
## Files Modified
### 1. `/index.js`
**Changes**:
- Imported `NpmService`
- Added npm service initialization
- Registered two new MCP tools:
- `get_npm_package_info`
- `compare_npm_versions`
- Added handler methods:
- `handleGetNpmPackageInfo()`
- `handleCompareNpmVersions()`
- Comprehensive error handling
### 2. `/README.md`
**Changes**:
- Added npm tools to features list
- Documented both new tools with examples
- Added dependency management usage example
### 3. `/USAGE_EXAMPLES.md`
**Changes**:
- Added npm tools section
- Provided practical examples
- Showed integration with existing tools
### 4. `/CHANGELOG.md`
**Changes**:
- Added unreleased section
- Documented new enhancement
- Referenced issue #15
### 5. `/test/integration.test.js`
**Changes**:
- Added npm tools integration tests
- Tests real npm API interactions
- Validates formatting and comparison logic
## Tool Specifications
### Tool 1: get_npm_package_info
**Input Schema**:
```json
{
"packageName": "string (required)"
}
```
**Returns**:
- Package name and description
- Latest version
- All distribution tags (latest, beta, lts, etc.)
- License and author
- Homepage and repository links
- Dependency counts
- Engine requirements
- Publish dates
- Maintainer count
**Example Usage**:
```
What's the latest version of ember-source?
Get information about @glimmer/component
```
### Tool 2: compare_npm_versions
**Input Schema**:
```json
{
"packageName": "string (required)",
"currentVersion": "string (required)"
}
```
**Returns**:
- Current vs latest version comparison
- Update status (up-to-date or needs update)
- All available distribution tags
- Release dates for both versions
- Total available versions
- Upgrade recommendation
**Example Usage**:
```
I'm using ember-source 4.12.0, should I upgrade?
Compare my @glimmer/component 1.1.2 with latest
```
## Technical Details
### API Integration
- Uses public npm registry API: `https://registry.npmjs.org`
- No authentication required
- Handles rate limiting gracefully
- Comprehensive error messages
### Error Handling
- 404 errors for non-existent packages
- Network error handling
- Malformed response handling
- User-friendly error messages
### Data Processing
- Parses complex npm registry response
- Extracts relevant information
- Formats for readability
- Handles missing/optional fields
## Testing
### Unit Tests
- 12 tests in npm-service.test.js
- All passing
- Covers main functionality and edge cases
### Integration Tests
- 2 tests added to integration.test.js
- Tests real npm API calls
- Validates end-to-end functionality
### Manual Testing
- manual-npm-test.js for quick verification
- Tests all major functions
- Demonstrates error handling
## Dependencies
**No new dependencies added!**
- Uses existing `node-fetch` package
- Pure JavaScript implementation
- No breaking changes to existing code
## Use Cases Solved
1. **Version Checking**: Quick lookup of latest package versions
2. **Upgrade Planning**: Compare current versions with latest
3. **Dependency Audits**: Check multiple packages for updates
4. **Compatibility**: Verify package compatibility via dependencies
5. **Pre-release Tracking**: Check beta/canary versions
6. **Package Discovery**: Explore package metadata and docs
## Future Enhancements (Potential)
1. Cache npm responses to reduce API calls
2. Add support for version ranges (^, ~)
3. Integrate with package-lock.json parsing
4. Add security vulnerability checking
5. Support for private npm registries
6. Batch operations for multiple packages
## Addresses Issue #15
This implementation fully addresses [Issue #15](https://github.com/ember-tooling/ember-mcp/issues/15):
- ✅ Gets latest stable version
- ✅ Gets all current information about a package
- ✅ Helps agents upgrade dependencies
- ✅ Comprehensive package data
- ✅ Well-documented and tested
## Example Agent Workflows
### Workflow 1: Simple Version Check
1. User: "What's the latest ember-source?"
2. Agent calls: `get_npm_package_info("ember-source")`
3. Returns: Latest version and key details
### Workflow 2: Upgrade Decision
1. User: "I'm on ember-source 4.8.0, should I upgrade?"
2. Agent calls: `compare_npm_versions("ember-source", "4.8.0")`
3. Shows comparison, dates, recommendation
4. May call `get_ember_version_info` for migration guide
### Workflow 3: Full Dependency Audit
1. User provides package.json
2. Agent parses dependencies
3. Calls `compare_npm_versions` for each
4. Summarizes what needs updating
5. Provides upgrade recommendations
## Code Quality
- ✅ Follows existing code style
- ✅ Comprehensive error handling
- ✅ Well-documented with JSDoc
- ✅ No linting errors
- ✅ All tests passing
- ✅ No breaking changes
## Documentation
- ✅ README updated
- ✅ USAGE_EXAMPLES updated
- ✅ CHANGELOG updated
- ✅ New comprehensive examples doc
- ✅ Inline code documentation
