Read one group, with its members

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

The description adds meaningful behavioral detail beyond the annotations: member resolution to names/ids when in the same address book, and the fallback behavior of reporting unresolvable members as references. This goes beyond what readOnlyHint/idempotentHint already communicate.

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 two sentences, front-loads what the tool returns, and adds only valuable resolution details. No redundant or filler wording is present.

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 simple read-one-group operation with complete schema coverage, an output schema, and annotations covering safety and idempotency, the description is fully sufficient. It even clarifies an edge case about unresolvable member references.

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 input schema fully describes the single `id` parameter with sources like list_contacts, search_contacts, list_groups, or list_changes. The description adds no additional parameter-specific meaning, but with 100% schema coverage 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?

The title states a specific verb and resource: 'Read one group, with its members'. The description elaborates precisely on what is returned—a group card and its contacts—making the tool's purpose unambiguous and distinct from siblings like get_contact or list_groups.

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 clearly indicates this tool is for retrieving a single group along with its member contacts. It does not explicitly name alternatives or exclusions, but the context makes it obvious when to use this tool versus list_groups or get_contact.

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