Leaderboard/emailens-mcp
MCP ServerScored via MCP protocol probing: initialize handshake, tools/list conformance, and ping + tool invocation performance.

emailens-mcp

# @emailens/mcp MCP server for email compatibility analysis. Analyze, preview, diff, and fix HTML emails across 15 email clients — plus capture real screenshots and create shareable links with an optional API key. Built on [`@emailens/engine`](https://github.com/emailens/engine). ## Install ```bash npx -y @emailens/mcp ``` ## Setup ### Claude Desktop Add to `claude_desktop_config.json`: ```json { "mcpServers": { "emailens": { "command": "npx", "args": ["-y", "@emailens/mcp"] } } } ``` ### Claude Code ```bash claude mcp add emailens -- npx -y @emailens/mcp ``` ### With API Key (optional — unlocks screenshots + sharing) ```json { "mcpServers": { "emailens": { "command": "npx", "args": ["-y", "@emailens/mcp"], "env": { "EMAILENS_API_KEY": "ek_live_..." } } } } ``` Get your free API key at [emailens.dev/settings/api-keys](https://emailens.dev/settings/api-keys). ## Tools ### Local Tools (no account needed) #### `preview_email` Full email compatibility preview — transforms HTML for 15 clients, analyzes CSS, generates scores, simulates dark mode, checks inbox preview and email size. | Parameter | Type | Required | Description | |---|---|---|---| | `html` | string | Yes | Email HTML source | | `clients` | string[] | No | Filter to specific client IDs | | `format` | enum | No | `"html"`, `"jsx"`, `"mjml"`, `"maizzle"` | #### `analyze_email` Quick CSS compatibility analysis — returns per-client scores and warnings. Faster than `audit_email` when you only need CSS compatibility. | Parameter | Type | Required | Description | |---|---|---|---| | `html` | string | Yes | Email HTML source | | `format` | enum | No | Input format | #### `audit_email` Comprehensive quality audit — CSS compatibility, spam scoring, link validation, accessibility, images, inbox preview, size (Gmail clipping), and template variables. | Parameter | Type | Required | Description | |---|---|---|---| | `html` | string | Yes | Email HTML source | | `format` | enum | No | Input format | | `skip` | string[] | No | Checks to skip (e.g. `["spam", "images"]`) | #### `fix_email` Generate a structured fix prompt for compatibility issues. Returns markdown with fix instructions that the AI can apply directly. | Parameter | Type | Required | Description | |---|---|---|---| | `html` | string | Yes | Email HTML to fix | | `format` | enum | No | Controls fix syntax | | `scope` | enum | No | `"all"` or `"current"` | | `selectedClientId` | string | No | Client ID for scoped fixes | #### `list_clients` List all 15 supported email clients with IDs, names, engines, and dark mode support. #### `diff_emails` Compare two email HTML versions — shows score changes, fixed issues, and introduced issues per client. | Parameter | Type | Required | Description | |---|---|---|---| | `before` | string | Yes | Original email HTML | | `after` | string | Yes | Modified email HTML | | `format` | enum | No | Input format | #### `check_deliverability` Check email deliverability for a domain — SPF, DKIM, DMARC, MX, BIMI records with a score and actionable issues. | Parameter | Type | Required | Description | |---|---|---|---| | `domain` | string | Yes | Domain to check (e.g. `"company.com"`) | ### Hosted Tools (require `EMAILENS_API_KEY`) #### `capture_screenshots` Capture real email screenshots across 15 clients in real browsers. Screenshots are hosted on CDN. | Parameter | Type | Required | Description | |---|---|---|---| | `html` | string | Yes | Email HTML source | | `format` | enum | No | Input format | | `clients` | string[] | No | Filter clients | | `modes` | string[] | No | `["light"]`, `["dark"]`, or `["light", "dark"]` | | `title` | string | No | Name for the preview | Free plan: 30 previews/day. [Sign up](https://emailens.dev?ref=mcp) #### `share_preview` Create a shareable link. Recipients see the full analysis without an account. | Parameter | Type | Required | Description | |---|---|---|---| | `html` | string | Yes | Email HTML source | | `title` | string | No | Display title | | `format` | enum | No | Input format | Requires Dev plan ($9/mo). Share links expire after 7 days (Dev) or never (Pro). ## Supported Email Clients (15) | Client | ID | Dark Mode | Notes | |---|---|---|---| | Gmail | `gmail-web` | Yes | | | Gmail Android | `gmail-android` | Yes | | | Gmail iOS | `gmail-ios` | Yes | | | Outlook 365 | `outlook-web` | Yes | | | Outlook Windows | `outlook-windows` | No | | | Outlook Windows Legacy | `outlook-windows-legacy` | No | Deprecated Oct 2026 | | Outlook iOS | `outlook-ios` | Yes | New in v0.4.0 | | Outlook Android | `outlook-android` | Yes | New in v0.4.0 | | Apple Mail | `apple-mail-macos` | Yes | | | Apple Mail iOS | `apple-mail-ios` | Yes | | | Yahoo Mail | `yahoo-mail` | Yes | | | Samsung Mail | `samsung-mail` | Yes | | | Thunderbird | `thunderbird` | No | | | HEY Mail | `hey-mail` | Yes | | | Superhuman | `superhuman` | Yes | | ## Development ```bash bun install bun run build bun test bun run typecheck ```

50/100
Operational Score
Score Breakdown
Availability30/30
Conformance10/30
Performance10/40
Key Metrics
Uptime 30d
100.0%
P95 Latency
296ms
Conformance
Fail
Trend
Stable
What's Being Tested
Availability
HTTP health check to the service endpoint
Responded with HTTP 404 in 210ms
Conformance
MCP initialize handshake + tools/list
MCP initialize handshake failed
Performance
MCP ping + zero-arg tool invocation benchmarking
P95 latency: 296ms, task completion: 0%
Improvement Tips
  • -Fix MCP initialize handshake errors
Recent Probe Results
TimestampStatusLatencyConformance
Apr 10, 2026success210.6msPartial
Apr 10, 2026success187.5msPartial
Apr 10, 2026success296msPartial
Source Registries
smithery
First Seen
Apr 10, 2026
Last Seen
Apr 10, 2026
Last Probed
Apr 10, 2026
emailens-mcp — Chiark Agent Quality Index