List Group Members

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

Annotations already mark readOnlyHint, openWorldHint, and idempotentHint true; the description adds meaningful behavioral detail: membership visibility is governed by the group setting, and 403 is an authorization outcome rather than a malfunction. It also states what entries contain (emails and roles), which helps the caller interpret results.

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, each earning its place: purpose, visibility/error interpretation, and output contents with a cross-tool tip. The most important behavioral caveat is front-loaded immediately after the purpose. No fluff.

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?

With full schema coverage, useful annotations, and an output schema present, the definition is complete. It even addresses the most likely failure mode (403) and gives a pointer for a natural follow-up task (resolving emails to names). Nothing critical is missing.

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% for all three parameters (group_email, max_results, user_google_email), so the schema already carries the semantic load. The description adds no extra parameter-specific meaning beyond the schema, so the baseline 3 is appropriate.

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?

Description uses a precise verb-resource pair: 'List the members of a Google Group', and disambiguates the API family (Cloud Identity Groups API). The title/name alone already says this, so the description reinforces it rather than restates it, and the 403/visibility notes give extra operating context.

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 explains the usefulness context: if you need to view group membership and understand visibility limitations. It also points to search_directory_people for email-to-display-name resolution. It does not explicitly state alternatives for membership listing, but no close sibling exists, so this is sufficient.

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