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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the useful context that the tool is for resolving unknown user ids, but it does not detail behavior such as what is returned or ordering. The output schema exists, which lowers the burden.

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 concise sentence with no filler, and the condition is front-loaded. It loses a point because it relies on the title to convey the actual action (listing members), making the standalone description slightly indirect.

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-only lookup with an output schema, the description and annotations provide enough context for an agent to invoke it correctly. The required householdId is documented in the schema, and the description tells the agent exactly the scenario in which the tool is needed. It is complete but not unusually rich.

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?

Both parameters have descriptions in the schema, so schema description coverage is 100%. The tool description itself adds no parameter-level meaning beyond what the schema provides, matching the baseline score for full schema coverage.

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 is condition-driven rather than a direct statement, but it clearly implies the tool lists household members to reveal their Familia user ids. It focuses on the use case (assignment/ownership/sharing), which distinguishes it from the sibling list_households tool. A more explicit 'List members of a household' phrasing would make it a 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 explicitly states when to use the tool: when a task/plan must be assigned, owned by, or shared with a named household member whose user id is unknown. It does not name an alternative or state when not to use it, but the condition is precise and actionable.

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