mail_create_draft

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

With no annotations, the description carries the full burden of behavioral disclosure. It only reveals that the email is not sent; it fails to mention that this persists a draft, may require authentication, or that reply/reply_all/forward modes depend on a sourceMessageId. In contrast to a simple read tool, this mutation's side effects are largely undisclosed.

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 sentence with no wasted words and it front-loads the action. It is appropriately brief for conveying the core purpose, though for a tool with this many parameters it is nearly too terse to be genuinely helpful. It earns its place but nothing more.

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 tool is complex: 11 parameters, nested objects, enums, and no output schema. The one-line description omits crucial context, such as the requirement of sourceMessageId for reply/forward modes, the role of comment/body in those modes, the meaning of mailboxScope, and what the tool returns after creating the draft. An agent cannot correctly invoke this tool reliably from the description alone.

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%, so the description must compensate across the 11 parameters. It only paraphrases the mode enum ('new/reply/reply-all/forward'), providing no meaningful detail on recipients, body, importance, mailboxScope, comment, or sourceMessageId. The one piece of parameter info is redundant with the schema and leaves the remaining parameters unexplained.

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 states a clear verb and resource: 'Create a ... draft', and it enumerates the possible draft types. The word 'without sending' distinguishes this from any send operation, though it does not explicitly contrast with the sibling mail_update_draft. Still, the core purpose is 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: use this when a draft is needed and should not be sent immediately. However, it provides no explicit guidance on when to prefer a sibling (e.g., mail_update_draft for modifying an existing draft) or when a different mode is required. The 'without sending' phrasing gives context but no exclusions or alternatives.

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