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

The annotations only indicate that the operation is not read-only and not destructive. The description adds crucial behavior: every field is optional and omitted fields are untouched, passing null for full_name clears it rather than omitting it, and theme cannot be null because 'system' represents following the OS. These details go well beyond what the annotations provide.

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 concise sentences deliver purpose, update semantics, and the null-vs-omit distinction without redundancy. The most important usage rule is stated up front, and every sentence earns its place. It is tightly structured and immediately actionable.

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 two-parameter optional-field update tool with an output schema, the description fully covers what an agent needs: what the tool does, which fields exist, how optionality works, the special null behavior for full_name, and the meaning of the 'system' theme. No critical behavioral gap remains.

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%, so both parameters are already documented well. The description adds value by summarizing the shared optionality rule and explicitly distinguishing null from omission for full_name, which reinforces and generalizes the schema descriptions. It does not introduce new parameter-level details not present in the schema, hence a 4 rather than 5.

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 opens with a specific verb and resource: 'Set or clear your own name, or change your dashboard theme.' It clearly identifies the two distinct operations and states that it operates on the caller's own profile, which distinguishes it from sibling tools like update_company or change_member_role.

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 phrase 'your own name' and 'dashboard theme' establishes clear usage context for self-profile updates, and the optional-field semantics clarify how to perform partial updates. However, it does not explicitly name alternatives or state when not to use this tool, such as for changing other members' roles, so it falls just short of a 5.

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