get-mail-message-mime

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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description is consistent. It adds value by specifying the return type ('MIME stream as text'), including headers/attachments, and warning about fetchAllPages potentially returning enormous payloads—beyond what annotations provide.

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 compact with a clear first sentence, followed by a tip that adds context but somewhat redundantly restates the core purpose. No wasted words, but the tip could be trimmed. Front-loaded purpose and immediate actionable guidance.

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 read-only download tool with 5 parameters and no output schema, the description covers purpose, usage scenario, return type, and how to obtain the required ID. It warns about the risk of large payloads via fetchAllPages. It does not explain failure modes or the behavior of includeHiddenMessages, but those are covered in the schema, so completeness is adequate.

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 coverage is 100% with detailed parameter descriptions (e.g., 'messageId' explains the naming and source, 'fetchAllPages' warns about large payloads). The description adds a tip about finding the message id earlier but does not enhance parameter understanding beyond the schema. 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 action ('Download the raw MIME source'), the resource (Outlook email message), and the method (by message ID). It explicitly differentiates from similar tools like get-mail-message (JSON retrieval) and gives a concrete use case (archiving to .eml).

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?

It provides a clear use case ('when archiving an email to disk') and tells the agent to find the message id with list-mail-messages first. However, it does not explicitly mention alternatives like get-mail-message, so the agent must infer that this is for raw MIME rather than structured data.

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