list_identitiesList the addresses this mailbox can send as, and which one is used by default. Pass one of them as from on send_email, reply_email, forward_email or draft_email to send as that address instead of the default. Addresses are added by the mailbox owner in their account, not through this connector, and the mail server still decides whether it will carry one.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the readOnly and idempotent hints, the description adds important behavioral context: identities are added by the mailbox owner outside the connector, and the mail server ultimately decides whether it will carry one. It also discloses that one address is the default, which is a meaningful detail for agents.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three sentences with no redundancy. The first sentence front-loads the core purpose, the second explains how to use the result, and the third adds a caveat about external limitations. Every sentence earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only, zero-parameter tool with no output schema, the description fully covers what is returned (the addresses and the default), how to use the result (as `from` in sending tools), and external constraints (owner-managed addresses, server decision). No critical information is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool has zero parameters, so parameter semantics are not applicable. The description appropriately focuses on output usage instead, and the baseline of 4 for zero-parameter tools applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific action ('List the addresses this mailbox can send as') and identifies the resource (send-as addresses) and the default selection. This clearly distinguishes it from siblings like list_mailboxes, which lists mailboxes rather than identities.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives clear context by explaining that the returned addresses can be passed as `from` on send_email, reply_email, forward_email, and draft_email to override the default. It doesn't explicitly mention alternatives or when-not-to-use, but the intended usage is evident and practical.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Most tools target clearly distinct actions, but there are several close pairs that require careful reading: check_bounces vs check_receipts, list_emails vs search_emails, and the send/reply/forward vs draft_email/draft_reply/draft_forward families. The descriptions are strong enough that a careful agent can disambiguate, but the boundaries are not always obvious from the tool names alone.
Every tool uses a consistent snake_case verb_noun convention, such as check_bounces, list_mailboxes, send_email, and update_draft. Related operations use parallel forms like mark_read/mark_unread and flag_email/unflag_email, making the naming predictable and coherent.
With 28 tools, this exceeds the 25+ threshold where a tool set starts to feel too heavy. Email is a broad domain and many tools are individually justified, but the surface could be consolidated, especially the draft_forward/draft_reply/draft_email and send_email/reply_email/forward_email variants.
The core email lifecycle is thoroughly covered: send, read, search, move, delete, drafts, replies, forwards, folders, flags, attachments, upload links, contacts, identities, deliverability, bounces, and receipts. The main gap is that permanent deletion is referenced as a separate operation but no such tool is actually provided, and contact/identity management is effectively read-only.