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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds value beyond them by disclosing the ordering ('soonest first'), the payload fields (visits used this year, next booked visit, overdue flag), and explicitly that no booking occurs.

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?

A single dense sentence covering scope, sort order, and returned fields, followed by a short clarifying clause. The scope qualifier is front-loaded; slightly heavy enumeration of return fields is the only minor cost.

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?

With no input parameters and no output schema, the description carries the burden of describing the result, and it does so by naming the four data points returned and their order. Sufficient for an agent to call and interpret the tool, though the partner-account scoping is not tied to any input parameter (there is none), leaving selection context implicit.

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 tool takes zero parameters, so the baseline is 4 and there is no parameter semantics to explain. Nothing in the description misrepresents or omits an input contract.

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?

Specifies the verb+resource precisely: 'serviced accounts due a maintenance visit under their agreed visits per year' relative to a partner account, which separates it from list_partner_maintenance_visits (a list of visits) and get_partner_maintenance_overview. It does not name a sibling directly, so it is clear but falls short of explicit differentiation.

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?

'Suggestions only; nothing is booked' tells the agent this is advisory planning output rather than an action, which is genuine guidance. However, it never states when to choose this over list_partner_maintenance_visits, list_partner_maintenance_alerts, or get_partner_maintenance_overview, so selection is left to inference.

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