mark_read

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only restates the state change and does not mention idempotency, permissions, effects on unread counts, or why include_raw exists. There is no contradiction, but the disclosure is minimal.

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?

The description is a single, front-loaded sentence with no filler, making it easy to parse. However, its brevity partly stems from omitting necessary behavioral and parameter details.

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 tool with 3 parameters, no annotations, and no output schema, this description is too thin. It does not explain how to target the message, whether mailbox is needed, or what include_raw does, leaving an agent under-informed.

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?

Schema description coverage is 0% and the description names no parameters. message_id, mailbox, and include_raw are left completely unexplained, with include_raw being especially non-obvious for a 'mark as read' operation.

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 clear action ('mark') and resource ('a message') with an explicit resulting state ('read'), so an agent can immediately understand the tool's function. It does not explicitly differentiate from siblings like mark_unread or batch_mark_read, but the read/unread distinction is evident from the name and description.

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?

There is no guidance on when to use this tool versus mark_unread, batch_mark_read, or other message-related tools. The required singular message_id implies single-message use, but the description never states this or any exclusions.

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