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

Annotations already declare openWorldHint=true, idempotentHint=false and destructiveHint=false, so the risky bits are partly covered. The description adds genuinely new context: mail is sent from a branded sender, private pages get per-address access codes, and the call consumes the plan's daily email quota — a real rate-limit disclosure. It stops short of saying what happens on partial failure (e.g., one bad address).

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?

Three short sentences, front-loaded with the core action, then the private-page nuance, then the quota cost. Nothing is redundant with the title or the schema.

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?

This is a mutating, open-world send with no output schema, so the description should say what a successful call yields or how failures surface (and it could point to get_delivery_status). It covers cost and audience behavior well but leaves the agent without any expectation of the response.

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 50%, so the description has to carry some weight: it explains that on a private page each address in `to` receives its own access code, which meaningfully links `to` to `code_max_uses`. However `request_page_id` and `message` are never mentioned, and the description adds no format or validation detail for addresses beyond the schema's 'up to 10'.

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 concrete verb and resource: 'Email a file request to people from the account's branded sender.' An agent understands exactly what action occurs and the delivery channel. It does not, however, distinguish itself from closely related siblings such as post_request_link, send_share_link, or issue_request_code.

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 explicit statement of when to use this versus any of its siblings, and no prerequisites (e.g., page must be open, whether a private page is required for codes to make sense). The quota sentence is a constraint, not usage guidance. The agent must infer the correct choice from the name alone.

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