save_attachment

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

Annotations already disclose destructiveHint=true and readOnlyHint=false, so the agent knows it's a mutating, destructive operation. The description adds no additional behavioral context such as whether files are overwritten, permissions required, or side effects. It merely repeats the obvious 'save' action without extra transparency.

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, clear, front-loaded sentence with no wasted words. It is appropriately brief, though it sacrifices necessary detail. The structure is clean, but the brevity contributes to the lack of context.

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 that writes a file (with destructiveHint and an output schema), the description is too sparse. It omits any mention of return values (though output schema may cover that), overwriting behavior, or prerequisites. Given the moderate complexity (3 parameters) and the availability of annotations and output schema, the description should provide more operational context but does not.

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 explain parameters but does not. It vaguely references 'one attachment from a message' but fails to mention filename, message_id, or destination explicitly. This leaves the agent without crucial details about what these parameters mean or how they relate to the action.

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 clearly states the action (save) and the resource (one attachment from a message) with a destination (local folder). It distinguishes from siblings like list_attachments and get_message by focusing on saving. However, it does not explicitly mention that the attachment is identified by filename and message_id, so it's not fully specific.

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?

No guidance is provided on when to use this tool versus alternatives such as list_attachments or open_in_mail. The description is a bare statement of functionality without any context, exclusions, or conditions.

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