gmail_get_send_as

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint, so the trailing "Read-only." is redundant. The one sentence that earns its place is "Signature HTML is untrusted content", which flags a prompt-injection risk the annotations do not express. Beyond that, nothing about completeness of the alias set or permission requirements is disclosed.

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, front-loaded sentences: what it returns, the security caveat, then the safety profile. Zero filler and the most decision-relevant information comes first.

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 zero-parameter read tool with rich annotations and no output schema, the description covers the essentials, including a partial sketch of return fields (display names, signatures). Only the absence of any note on the primary-address entry or required auth scope keeps it from a 5.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the schema is empty by design. Baseline is 4; the only missing nuance is that the call returns all aliases with no filtering option.

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 ("Lists send-as aliases") and names the returned fields (display names and signatures), which lets an agent distinguish it from gmail_get_profile or gmail_list_labels. No sibling is explicitly named as an alternative, so it falls short of 5.

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 never says when to call this versus gmail_get_profile, nor does it state any prerequisite (e.g. settings scope). The usage is only inferable from the name and the word "Lists"; no exclusions or alternatives are given.

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