Checks HTML email against 21 email clients: rendering previews, per-client CSS compatibility, dark mode simulation, fixes and deliverability checks.
Setup
Choose your client, copy the config, then fill in any required environment variables.
Local
claude mcp add emailens --env EMAILENS_API_KEY='<EMAILENS_API_KEY>' -- npx -y @emailens/mcp~/.codex/config.toml
[mcp_servers.emailens]
command = "npx"
args = ["-y", "@emailens/mcp"]
env = { EMAILENS_API_KEY = "<EMAILENS_API_KEY>" }
# codex mcp add emailens --env EMAILENS_API_KEY='<EMAILENS_API_KEY>' -- npx -y @emailens/mcp~/.cursor/mcp.json
{
"mcpServers": {
"emailens": {
"command": "npx",
"args": [
"-y",
"@emailens/mcp"
],
"env": {
"EMAILENS_API_KEY": "<EMAILENS_API_KEY>"
}
}
}
}.vscode/mcp.json
{
"servers": {
"emailens": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@emailens/mcp"
],
"env": {
"EMAILENS_API_KEY": "<EMAILENS_API_KEY>"
}
}
}
}~/.gemini/settings.json
{
"mcpServers": {
"emailens": {
"command": "npx",
"args": [
"-y",
"@emailens/mcp"
],
"env": {
"EMAILENS_API_KEY": "<EMAILENS_API_KEY>"
}
}
}
}claude_desktop_config.json
{
"mcpServers": {
"emailens": {
"command": "npx",
"args": [
"-y",
"@emailens/mcp"
],
"env": {
"EMAILENS_API_KEY": "<EMAILENS_API_KEY>"
}
}
}
}.trae/mcp.json
{
"mcpServers": {
"emailens": {
"command": "npx",
"args": [
"-y",
"@emailens/mcp"
],
"env": {
"EMAILENS_API_KEY": "<EMAILENS_API_KEY>"
}
}
}
}Remote
claude mcp add --transport http emailens https://emailens.dev/api/mcp~/.codex/config.toml
[mcp_servers.emailens]
url = "https://emailens.dev/api/mcp"
# codex mcp add emailens --url https://emailens.dev/api/mcp~/.cursor/mcp.json
{
"mcpServers": {
"emailens": {
"url": "https://emailens.dev/api/mcp"
}
}
}.vscode/mcp.json
{
"servers": {
"emailens": {
"type": "http",
"url": "https://emailens.dev/api/mcp"
}
}
}~/.gemini/settings.json
{
"mcpServers": {
"emailens": {
"httpUrl": "https://emailens.dev/api/mcp"
}
}
}claude_desktop_config.json · Customize › Connectors › Add custom connector
{
"mcpServers": {
"emailens": {
"command": "npx",
"args": [
"-y",
"mcp-remote",
"https://emailens.dev/api/mcp"
]
}
}
}.trae/mcp.json
{
"mcpServers": {
"emailens": {
"url": "https://emailens.dev/api/mcp"
}
}
}Environment variables
EMAILENS_API_KEY
Replace the placeholders with your own credentials and keep them out of version control.