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

With no annotations, the description carries the full burden. It clearly discloses the primary behavior (save, not send), but it does not mention any side effects, prerequisites, or error conditions. For a simple draft-saving tool, this is adequate but minimal.

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 a single, front-loaded sentence. Every word earns its place: it names the tool's action, the resource, and the key differentiator (not sending). It is appropriately concise.

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?

The description covers the core purpose and differentiates from send, but it lacks guidance on when to use this versus save_outlook_draft, does not explain parameters, and provides no information about return values or prerequisites. Given the tool's simplicity and lack of annotations, it is minimally complete but has clear gaps.

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 the description provides no additional meaning for the parameters (to, subject, body). The parameter names are self-explanatory, but the description fails to compensate for the lack of schema descriptions, so it adds no value beyond the raw schema.

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 a specific verb and resource: 'Save Gmail draft without sending.' It explicitly differentiates from send_email by noting 'without sending' and from save_outlook_draft by specifying 'Gmail.'

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 a draft is needed instead of sending, but it does not explicitly mention alternatives like save_outlook_draft or send_email, nor does it provide when-not-to-use guidance.

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