Mailbox MCP

Mark emails as read

mark_read

Idempotent

Mark messages as read. Reading a message through this connector does NOT mark it read, deliberately, so this is the separate act that does - run it when the person asks for it, never because you have looked at something. Pass every message you want marked in ONE call. THE RESULT IS VERIFIED RATHER THAN ASSUMED: the flags are read back off the server afterwards, so a message that could not be changed is named individually instead of being folded into a success, and a batch really can half-succeed. A uid only means something in the folder it came from, so pass mailbox whenever the uids did not come from INBOX - the commonest way to get this wrong is to search Archive and then mark read against the default. Marking a message that is already read changes nothing and is not an error. mark_unread is the undo.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`uids`	Yes	The UIDs to act on, from list_emails or search_emails. Pass EVERY message you want changed in ONE call - this tool acts on the whole set in a single operation, and doing it that way costs the user one call instead of one per message. Up to 500 at a time. A single message is simply a one-element array.
`mailbox`	No	IMAP folder name. Defaults to INBOX.

Schema Changelog

Changes observed during successful MCP inspections. Dates show when Glama detected each change.

First observedSep 5, 2026

TDQS

A4.9/5.0

Behavior5/5

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

The description adds substantial behavioral context beyond the annotations: the deliberate no-read side effect of read_email, verified read-back rather than assumed success, partial batch failure with individually named messages, and idempotent behavior for already-read messages. These details are crucial for an agent to reason about side effects and outcome reliability, and they do not contradict the annotations.

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

Conciseness5/5

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

The description is long but every sentence earns its place: purpose, intentional read behavior, batching, verification, folder scoping, idempotency, and undo. It is front-loaded with the core purpose and then layers caveats in a logical order with no fluff or redundant filler.

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

Completeness5/5

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

For a two-parameter mutation with no output schema, the description covers all essential operational context: when to use it, how to batch uids, how to handle non-INBOX mailboxes, partial-failure possibilities, and idempotency. An agent can confidently select and invoke the tool correctly without needing additional information.

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

Parameters4/5

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

Schema coverage is 100% and the schema already documents both parameters thoroughly. The description adds genuine beyond-schema semantics by explaining that a UID only means something in the folder it came from, so mailbox must be passed for non-INBOX uids. It also reinforces the single-call batching guidance, but the uids semantics mostly mirror the schema, which is why this is a 4 rather than a 5.

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?

The description opens with a clear specific verb-resource statement: 'Mark messages as read.' It distinguishes itself from read_email and mark_unread by explaining that reading through the connector deliberately does NOT mark read, and naming mark_unread as the undo. There is no ambiguity about what this tool does or how it differs from its siblings.

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

Usage Guidelines5/5

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

It explicitly states when to invoke the tool: when the person asks for it, never because you have looked at something. It instructs passing every message in ONE call and warns about the common mailbox pitfall when uids did not come from INBOX. It also names mark_unread as the undo, giving clear alternative and exclusion guidance.

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

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TDQS

A4.3/5.0

Disambiguation4/5

Most tools target clearly distinct actions and resource types, and the near-overlapping pairs (archive_email vs move_email, check_bounces vs check_receipts) are explicitly cross-referenced in their descriptions. However, the delivery-status pair genuinely overlaps — both scan inbound mail to answer "did my message get there?" — and archive_email is functionally a role-aware move_email, so an agent could still select the wrong one without careful reading.

Naming Consistency4/5

Virtually every tool follows a consistent verb_noun pattern with clear prefix families (check_*, create_*, draft_*, list_*, mark_*, read_*). The single outlier is not_junk, which breaks the mark_* symmetry of its counterpart mark_junk and is not a standard verb-noun construction, though it remains perfectly readable.

Tool Count3/5

31 tools is firmly in the heavy range, though email is a genuinely broad domain spanning send/reply/forward, three draft variants, folder management, flags, junk handling, and diagnostics. Real consolidation was possible — check_bounces and check_receipts could be one delivery-status tool, archive_email is a special case of move_email, and the read-state/flag pairs could take boolean parameters — but each tool has a defensible job.

Completeness4/5

The core email lifecycle is thoroughly covered: send/reply/forward, three draft types plus draft editing, read/search/list/thread, full folder CRUD, move/archive/delete, flags, read state, junk handling, and file-upload intake. Minor gaps exist — there is no permanent-deletion or purge tool, no filter/rules management, and identity/contact maintenance is deliberately out of scope — but real user workflows can be completed without dead ends.

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