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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds non-obvious behavior beyond that: ambiguous matches are refused, exactly one identity is returned, and phone/email/street address are deliberately withheld. That refusal and output-scoping detail is genuinely useful and not derivable from the annotations.

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?

Three short sentences, zero filler, with the primary usage condition front-loaded and the behavioral caveats (refusal, withheld fields) trailing. Every sentence carries distinct 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?

An output schema exists, so the description is not obliged to explain the return shape, and it correctly spends its words on the refusal rule and the fields deliberately excluded from the response. Coverage is solid for a 3-optional-parameter resolver; the only gap is the absence of routing guidance to sibling lookup 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 100%, with each of the three parameters already carrying an example and the 'place' parameter documenting its own ambiguity refusal. The description restates the input modes but adds no syntax or format 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 ('resolve one enrolled local home-service business') and enumerates the three input modes (domain, place, phone). It distinguishes the tool as a single-entity resolver rather than a search, but never names the sibling tools (search_businesses, get_business) it contrasts with, so the differentiation is implied rather than explicit.

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?

It gives a clear triggering condition ('when the user wants to resolve one... business') and the qualifying inputs, so an agent knows the context in which to reach for it. There are no exclusions or explicit alternative routes (e.g., use search_businesses when the match is ambiguous or when several businesses are wanted), which keeps it 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.