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

Goes well beyond the annotations: discloses the up-to-5 cap, that input is trimmed, duplicates and the business name itself are dropped, that an empty list resets to name-only, and that the effect reaches past answers. This is rich behavioral context the readOnly/idempotent/destructive hints alone do not convey.

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?

Front-loaded with the core action and effect, and nearly every clause carries information. It is densely packed but the clause about 'past weeks' answers' slightly interrupts the flow; still efficient overall.

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 single-parameter mutation with an output schema present, the description covers everything an agent needs to call it correctly: what it replaces, the limit, normalization behavior, reset semantics, permission scope, and related tools.

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 100% and the schema already gives a concrete example, so baseline is 3. The description adds genuine meaning not in the schema: the five-item ceiling and the trim/dedupe/drop-own-name normalization rules applied to the aliases parameter.

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 ('Replaces your business's other names') with the count limit, and the Related line names the sibling set_competitor_aliases, letting an agent separate business aliases from competitor aliases without opening schemas.

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?

Clearly establishes context: applies to business aliases, affects named rate and share of voice including past weeks' answers, and notes 'Any member can call it.' It does not, however, give explicit when-not conditions or contrast its use against set_competitor_aliases beyond the Related link.

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