# Agentmail Claude Code MCP Evaluation

**Category:** Email
**Score:** 75 (B)

This is the agent-readable Devtool Arena evaluation page for Agentmail on Claude Code MCP.

## Summary

| Metric | Value |
|--------|-------|
| Status | completed |
| Overall score | 75 |
| Grade | B |
| Eval score | 74 |
| Discovery score | 79 |
| Cost | $0.10 |
| Runtime | 4m 25s |
| Tool calls | 7 |
| Errors | 3 |
| Tokens used | 180705 |
| Success | Yes |

## Agent-Readiness Checklist

| Signal | Evidence |
|--------|----------|
| Context7 | Not found |
| llms.txt | Not found |
| MCP server | Not found |
| Typed SDK | Not found |
| OpenAPI | Not found |
| Agent skills | Not found |
| CLI | Not found |

## Evaluation Prompt

````text

# Task
Using the Agentmail MCP, perform email operations:

1. Discover available MCP tools and their capabilities
2. Create a new email inbox (or list available inboxes/domains)
3. Send an email with subject "Hello from [REDACTED:ORG] MCP Leaderboard" and body "This is a ***** email sent via the Agentmail MCP server." (If the recipient is blocked, send to any available address instead.)
4. List messages or check email status
5. Print all output as JSON

Use ONLY the MCP tools for all operations.

You MUST use the Agentmail MCP server to accomplish this task.
Use the MCP tools for the actual product operations. Do NOT use curl, fetch, raw HTTP requests, CLI commands, or SDK calls as substitutes.

Use the MCP tools' help/descriptions to understand what each tool does.
If you need additional context, check the documentation: https://github.com/agentmail-to/agentmail-mcp

## Setup
Do NOT assume the Agentmail MCP server is already installed or already running in this sandbox.
Review the installation and authentication details below before starting the task.

### Installation
Transport: `stdio`
Claude Code is configured to launch the `agentmail` MCP server over stdio using: `agentmail-mcp`
Stored MCP package hint: `agentmail-mcp`
Run this setup command in the sandbox before the agent launches the server: `npm install -g agentmail-mcp`
Bootstrap notes: Verified via `npm view agentmail-mcp`: real npm package, description 'stdio compatibility bridge for the hosted AgentMail MCP server', bin name `agentmail-mcp`, la***** version 1.1.0, docs link https://docs.agentmail.to/integrations/mcp. Ran `npm install -g agentmail-mcp` in this sandbox; `which agentmail-mcp` resolved to a real executable and `agentmail-mcp` launched without immediately erroring (consistent with an MCP stdio server that reads JSON-RPC on stdin and only needs AGENTMAIL_API_KEY when tools are actually invoked). Vendor GitHub README (agentmail-to/agentmail-mcp) documents the Claude Desktop/Code stdio config as command=npx, args=['-y','agentmail-mcp'], env={AGENTMAIL_API_KEY}. I instead pre-install the package via setup_commands and call the installed bin directly (command='agentmail-mcp') so the long-running launch step is a plain executable rather than an npx wrapper, per instructions to keep setup idempotent and keep the launch command out of setup_commands.

### Authentication
The following environment variables are already set in this environment: `AGENTMAIL_API_KEY`
The MCP server should read them automatically when it starts.

## Execution
1. The harness has already written the launch configuration for `agentmail`. Start with the task directly; do not rewrite agent settings, `.mcp-runtime.json`, or build a separate MCP client unless the connected server still fails after a normal retry.
2. You do not need to enumerate every MCP tool up front; inspect only the relevant tools you need. Agent-facing MCP tool names may be namespaced like `mcp__agentmail__<tool_name>`.
3. Complete the task described above using MCP tools for the actual product operations.
4. If the server fails to start or authenticate, debug the documented setup and retry. Do not fall back to raw HTTP, SDK, CLI, or manual JSON-RPC/MCP calls as a substitute for exposed MCP tools.

Work in the /home/daytona/app directory.
If you use Bash during setup or debugging, limit it to installation/configuration work and then return to MCP tools for the task itself.
If there are errors, debug and fix them until the task runs successfully.

## Summary
When you are done, write a JSON summary file to /home/daytona/app/results.json with this structure:
{
  "operations": [
    {"step": 1, "description": "What you did", "mcp_tool": "tool_name", "success": true/false, "output_summary": "brief result"},
    ...
  ],
  "overall_success": true/false,
  "notes": ["any relevant notes about the execution"]
}

````

## Grader Results

| Check | Passed | Weight | Score | Details |
|-------|--------|--------|-------|---------|
| Task | Yes | — | — | — |
| Llms Txt | Yes | — | 10 | — |
| Tool Count | Yes | — | 3 | — |
| Auth Method | Yes | — | 15 | — |
| Official Mcp | Yes | — | 5 | — |
| Output Schema | No | — | 0 | — |
| Error Messages | — | — | 0 | create_list_entry: Poor error message (generic or stack trace); connect_provider: Poor error message (generic or stack trace) |
| Tool Stability | Yes | — | 5 | — |
| Security Posture | — | — | 9 | — |
| Tool Api Mapping | — | — | 14 | — |
| Description Clarity | — | — | 14 | — |
| Tool Description Length | Yes | — | 4 | — |

## Run Artifacts

| Artifact | Value |
|----------|-------|
| Conversation turns | 11 |
| Tool call traces | 7 |
| Generated files | 1 |
| Exit code | — |
| Completed at | 2026-09-27T14:24:48.173445+00:00 |

### Generated Files

- /home/daytona/app/results.json

## Related Pages

- [Claude Code MCP leaderboard](/leaderboard/claudecode/mcp)
- [Compare Claude Code MCP companies](/leaderboard/claudecode/mcp/compare)
- [Agent Landscape](/leaderboard/discoverability)

Canonical URL: https://devtoolarena.com/claudecode/mcp/agentmail