read_email

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

Annotations already provide readOnlyHint=true and destructiveHint=false, so the description adds value by disclosing the implementation (Mail.app via AppleScript) and that it works without filesystem access. No contradictions.

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?

Two sentences, front-loaded with purpose followed by implementation detail. No wasted words or redundant information. Very concise and well-structured.

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?

Given the tool has only one parameter and no nested objects, the description adequately explains its purpose and behavior. However, it does not specify the return format (e.g., plain text body, headers, attachments), which is a minor gap for completeness, especially with no output schema.

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?

The input schema describes the parameter 'message_id' with examples and format. The tool description does not add any extra semantic meaning beyond what the schema already provides. With 100% schema coverage, baseline of 3 is appropriate.

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 tool reads the full body of an email using its RFC message-id, and distinguishes it from sibling tools like search_emails which return metadata. The verb 'read' and resource 'email' are specific and unambiguous.

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 when you have a message ID from search_emails or list_recent, and clarifies it works with IMAP/iCloud/Exchange. It does not explicitly state when not to use it or mention alternatives, but the context is clear enough for selection among siblings.

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