mark_read

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

Annotations already declare idempotentHint=true and destructiveHint=false. The description adds the boolean semantics (True/False) but no additional behavioral context such as effects on other tools or permissions. It does 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.

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

The description is a single sentence that immediately explains the tool's action and the boolean's meaning. Every word is necessary, with no filler or repetition.

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 simple tool with two parameters and strong annotations (idempotent, non-destructive), the description is sufficient. It could mention idempotence or prerequisites, but the annotation and simple schema make the tool easy to understand. No output schema means no need to describe returns.

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%, so the description must compensate for parameter meaning. It explains the 'read' parameter ('read=True or read=False') but adds nothing about message_id beyond what the schema already states (type string, required). This is partial compensation.

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 uses a specific verb ('Mark'), a clear resource ('a message'), and the exact state change ('read=True' or 'read=False'). This clearly distinguishes it from sibling tools like flag_message, move_message, or delete_message.

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 implies usage—setting read/unread status—but does not explicitly state when to use this tool versus alternatives or any exclusions. No guidance on when not to use it is provided, so it meets only the 'implied usage' level.

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