Open Mail Message

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

Annotations minimal (title only), so description should disclose behavior. It says 'open' but doesn't clarify if it opens in GUI, returns message content, or requires Mail.app to be running. Output schema exists but not described.

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?

Single sentence, concise, but lacks essential details. Could be restructured to front-load key info and add parameter explanations.

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?

With output schema, description should explain return value. Tool complexity is low, but missing parameter explanations and usage context makes it incomplete.

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 description adds no information about parameters. 'dry_run' and 'message_id' are unexplained; no format or semantics provided.

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?

Description clearly states the tool opens a Mail message by ID, using specific verbs and resource. Distinguishes from siblings like mail_search or mail_get_thread.

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 on when to use this tool versus alternatives such as mail_get_thread or mail_search. No mention of prerequisites or context.

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