AI agents · Claude

Zyntra MCP for Claude

Give Claude a test inbox it can read and nothing else. In Claude Code it is one command; in Claude Desktop and claude.ai it is a custom connector with your API key in a request header. Either way Claude gets five tools to read and delete test email, and no way to send any.

Start freeGet an API key
Claude Code
# Add the server for your user (all projects)
claude mcp add --transport http zyntra \
  https://mcp.zyntra.app/mcp \
  --header "X-API-Key: $ZYNTRA_API_KEY"

# Check that it connected
claude mcp list
.mcp.json (shared with a project)
{
  "mcpServers": {
    "zyntra": {
      "type": "http",
      "url": "https://mcp.zyntra.app/mcp",
      "headers": { "X-API-Key": "${ZYNTRA_API_KEY}" }
    }
  }
}

Get an API key in the Zyntra dashboard and export it as ZYNTRA_API_KEY. In a project's .mcp.json, the key stays an environment variable, so the file can be committed without it.

What happens to the email

  1. Your app sends it through its usual email provider, to an address on zyntramail.com.
  2. A real mail server receives it and stores it for your team, with its links pulled out of the HTML and text and its attachments kept.
  3. Your test reads it with one API request. Mail to an address you did not create in the dashboard is deleted after 1 day.

Claude Desktop and claude.ai

  1. Open Customize → Connectors, choose Add, then Add custom connector.
  2. Name it Zyntra and set the URL to https://mcp.zyntra.app/mcp.
  3. Under Request headers, add X-API-Key with your Zyntra API key, then save.

Prompts to start with

Limits to know about

  • get_last_email waits up to 30 seconds for the first email to an address; give the agent a fresh address per task so it never reads an older email.
  • Each tool call is one API request on your plan.
  • Mail to addresses you did not create in the dashboard is kept 1 day.
  • On Team and Enterprise plans, an organization owner adds custom connectors; members then connect them.

Questions

Can I put the server in claude_desktop_config.json?
That file is for local MCP servers. Zyntra's server is remote, so add it as a custom connector in Claude's settings.
Is it available on Claude's free plan?
Custom connectors work on every Claude plan; the free plan allows one.

Agentic testing

Claude Code signs up in a browser with Playwright MCP and reads the email.

Read the guide →

Cursor

The same server in Cursor's MCP settings.

Read the guide →

AI agents

What the five tools do, and why the inbox is receive-only.

Read the guide →

Give Claude a test inbox

Free plan. Connect the MCP server with one API key.

Start free