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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and openWorld, so the safety profile is covered. The description's only added behavioral fact is the $0.012 per-request price, which is real but thin and not enough to explain what 'raw' output entails (e.g., raw MIME vs parsed fields).

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?

It is short and front-loaded, but the pricing comment block is boilerplate that occupies most of the body without helping the agent invoke the tool. Nothing is bloated, yet nothing earns its place either.

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?

An output schema exists so return values need not be described, but the core ambiguity — how this differs from get_agentmail_inbox_message and what 'raw' means — is left entirely unresolved for a tool with many near-identical siblings.

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% and both required parameters (inbox_id, message_id) are documented in the schema itself. The description adds no meaning beyond that, so the baseline 3 applies.

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 is effectively the title restated: 'Get Raw Message' with no expansion of what 'raw' means or what resource is actually fetched. With dozens of sibling getters (get_agentmail_inbox_message, get_agentmail_inbox_message_attachment, etc.), the agent gets no basis for distinguishing this tool from the normal message getter.

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?

There is no when-to-use guidance, no mention of the alternative get_agentmail_inbox_message, and no note about when the raw representation is preferable. The only additional text is a pricing boilerplate block, which does not help selection.

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