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, so the safety profile is covered. The description adds useful behavioral context by stating the return is the complete original message with headers and encoded attachments, and that the MIME stream comes back as text.

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 front-loaded and compact, but the tip paragraph partly repeats the first sentence ('raw RFC 5322 MIME content', 'Returns the MIME stream as text'). The use case and message-id workflow add value; the redundancy keeps it from a 4.

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 single-resource retrieval tool, the description fully explains what is returned, why to use it, and how to obtain the required message ID. All optional parameters are documented in the schema, and no output schema exists, so the explicit "returns MIME stream as text" statement is sufficient.

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 100%, so the description does not need to re-explain parameters. It adds one useful workflow hint beyond the schema: 'Find the message id with list-mail-messages first.' This is above the baseline for fully schema-covered parameters.

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?

States a specific verb and resource: 'Download the raw MIME source (RFC 822 .eml content) of an Outlook email message by its message ID.' The mention of raw MIME vs the sibling get-mail-message clearly distinguishes it from a normal message fetch.

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?

Explicitly gives a use case: 'Use this when archiving an email to disk preserving all original headers, body, and inline-encoded attachments.' It also tells the agent to find the message id with list-mail-messages first. It does not explicitly mention when not to use it or contrast with get-mail-message, so it falls short of a 5.

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