fastpanel-mcp

mailbox_get

Read-onlyIdempotent

Retrieve a single mailbox by ID to inspect its redirects, aliases, quota, size, flags, and owner; passwords are not returned.

Instructions

Get one mailbox by id (full object: redirects, aliases, quota, size, flags, owner). Maps to GET /api/mail/box/{box_id} — note the different URL family from the list endpoint. The password is never returned — FastPanel has no endpoint that reveals it.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "box_id": "<box_id>"
    },
    "name": "mailbox_get"
  }
}

Input Schema

Name	Required	Description	Default
`box_id`	Yes	Mailbox id from mailboxes_list

Schema Changelog

Changes observed during successful MCP inspections.

Addedv1.3.0Nov 12, 2026

TDQS

A3.9/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, non-destructive, open-world behavior, so the safety profile is covered. The description adds real value beyond that by disclosing the exact field set returned and the important caveat that the password field is never included, which prevents a wasted call.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences, front-loaded with purpose and return contents, then caveats. The endpoint-mapping sentence is the weakest link for an agent-facing reader, but it does reinforce the distinction from the list endpoint and costs little space.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description correctly compensates by enumerating the returned fields, and the password caveat closes the main ambiguity for a mailbox read. The only residual gap is the unaddressed relationship to mailbox_password_get, which leaves a sibling-routing question open.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the single parameter already carries 'Mailbox id from mailboxes_list' plus an exclusiveMinimum constraint. The description's 'by id' adds no format, origin, or validation detail beyond what the schema states, so the baseline of 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Names a specific verb and resource ("Get one mailbox by id") and enumerates what comes back (redirects, aliases, quota, size, flags, owner), so an agent knows this is the single-object fetch rather than a list. It also pinpoints the underlying endpoint, making the resource unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied: the URL-family remark signals this is not the list call, and the schema points to mailboxes_list as the id source, but there is no explicit when-to-use statement. Worse, the blanket claim that FastPanel has no endpoint revealing a password may steer an agent away from the sibling mailbox_password_get, which the description never acknowledges.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.