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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds that output is a count per service and that availability is 'public locals', which is useful behavioral context beyond the annotations, though return shape details remain thin.

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 front-loaded sentences that waste little; the state-required/city-optional clause is the payload. The inline format examples ('new-jersey', 'florida') duplicate the schema and slightly bloat the text.

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 output schema, the description covers the return semantics ('count per service'), the input requirements, and the intended use case. An agent has everything needed to invoke and interpret this read-only tool.

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 both parameters are already documented with format rules and examples, so the description largely restates them ('state is required ... city is optional'). It adds the useful framing of omitting city for state-level availability, but that is also in the schema's city description.

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 ('Check which ... have public locals'), the resource (30 service categories), and the scoping dimension (US state or city), plus that a per-service count is returned. This distinguishes it from list_service_categories (no availability) and search_local_workers (worker listing, not availability).

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?

Gives clear context: 'Useful before searching, or to answer "can I get X done in Y?"'. It tells the agent when the tool applies but never names an alternative sibling or an exclusion condition (e.g., when to prefer list_service_categories or search_local_workers instead).

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