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

Beyond the readOnly/idempotent annotations, the description discloses the inclusion rule (only interval-based tasks qualify) and enumerates the excluded categories, plus what each result item reports (progress ratio, basis, upcoming flag, interval owner). That is substantive behavioral context an agent cannot get from annotations or the schema.

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 question and the ordering guarantee, then the inclusion rule, then result shape. Dense but waste-free; the mid-sentence clause listing exclusions via a double negative ('never appear') is slightly harder to parse than it needs to be.

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 annotations covering the safety profile, a fully documented parameter, and an output schema covering return structure, the description supplies exactly the missing pieces: what counts as due, what is filtered out, and what each item conveys. Nothing an agent needs to call it correctly is absent.

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 the single enum parameter is fully documented in the schema, including the 'due' default and mute ordering. The description adds no syntax or format detail about the status parameter, 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?

States a specific verb+resource (what maintenance is due across the user's current grinders and machines) and scopes it to the 'is anything due?' question, which clearly separates it from siblings like log_maintenance, set_maintenance_schedule, and get_maintenance_guides.

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 framing 'for "is anything due?"' gives a clear usage context and implies when to reach for this tool rather than scheduling or logging siblings. It never names an alternative explicitly or states when NOT to use it, so it falls 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.