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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: it is a partial update (unspecified fields are preserved) and it returns the updated department. It stops short of warning about side effects of reparenting (moving a department with children).

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?

Two short sentences, front-loaded with the operation type and resource, with zero filler. Every clause (WRITE, partial update, return value) carries information.

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 5-parameter mutation with full schema coverage and no output schema, the description covers the essentials: mutation type, partial-update behavior, and a return-value statement. It could be stronger on reparenting side effects and when to prefer create vs update, but nothing an agent needs to invoke it correctly 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% and every parameter has a docstring, including 'Omit to keep the current name' and where the id comes from. The description adds no parameter-level detail beyond the schema, so the baseline 3 applies.

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 states a specific verb and resource ('Rename or move one department'), leads with a WRITE marker, and clarifies single-department scope plus partial-update semantics. An agent can distinguish this from smarthr_create_department and smarthr_update_employee without opening a schema.

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 parenthetical 'partial update: only the fields you give change' implies the tool is for modifying existing departments rather than creating them, but it never names alternatives or states prerequisites (e.g., fetch id via smarthr_list_departments is only mentioned in the schema, not the description). Usage is implied rather than explicit.

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