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

No annotations are supplied, so the description carries the full burden. It does disclose two real behavioral traits beyond the schema: the operation is 'Read only', and a field worker sees only themselves (role-scoped visibility). It stays silent on permission requirements, what happens if shop hours or worker hours are unconfigured, and any rate/cost characteristics of the computation.

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?

The purpose is front-loaded, but the opening sentence is a long clause-heavy run-on that takes effort to parse ('open worker minutes inside shop hours (and each worker's own hours) minus time off...'). The trailing sentences are efficient and earn their place; the first one could be split for far better scanability.

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 an output schema present, the description is not obliged to explain return values, and it spends its words instead on computation semantics and the findTime equivalence, which is the right trade. A moderate-complexity read tool with five parameters and one required field is adequately covered, with the main missing piece being routing guidance against sibling capacity/slot 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 description coverage is only 40%, so the description needs to compensate. It adds genuine meaning for the two undocumented parameters: visit_minutes defaults to 120, and person_ids narrows to specific workers. It adds nothing for days or from beyond what the schema already states (default 5, shop time zone, default today).

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 names a specific computation: per-day open worker minutes (shop hours capped by worker hours, minus time off), booked minutes, percent booked, and how many visits of a given visit_minutes still fit. That is a concrete verb+resource, not a restatement of the name. It is less distinct from siblings than it could be — schedule_findTime is referenced only as an algorithm analogue, never as an alternative to choose between.

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?

Usage is implied rather than stated: 'next working days' plus the fit-count framing tells an agent this answers a how-much-room-is-left question. 'Give person_ids to check some workers' is a useful conditional hint. However, there is no explicit when-to-use or when-not versus schedule_findTime, schedule_openSlots, or schedule_list, which are the obvious competing reads.

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