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

Annotations already declare readOnlyHint=true, openWorldHint=false, and destructiveHint=false, so the safety profile is covered by structured data. The description adds genuine context beyond that: this returns a deliberately *short* card, and the structured profile is only present 'when available' — warning the agent that fields may be missing. It doesn't discuss rate limits or lookup-failure behavior, which keeps it at 4 rather than 5.

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 sentence with zero waste, and the routing decision (prefer get_provider_profile; use this only for…) is front-loaded so the agent sees the disambiguation rule before the field list.

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 return values needn't be explained, yet the description enumerates the card's contents anyway and flags that the structured profile is conditional. Combined with annotations covering the read-only, closed-world safety profile, an agent has everything needed to select and invoke this correctly.

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 both parameters documented (handle example, regNum example), so the schema carries the semantic load and the baseline is 3. The description reiterates the two lookup keys ('by handle or registration number') but adds no format, precedence, or mutual-exclusivity detail beyond what the schema already shows.

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 and resource (retrieve the short public directory card of one provider) and enumerates exactly what the card contains: bio, source URLs, X-verification status, entity type, community rating, structured profile. It explicitly names the sibling get_provider_profile as the tool for a different need, so an agent can disambiguate without opening either schema.

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 an explicit when-to-use rule ('for buying decisions prefer get_provider_profile') and a restrictive when-to-use-this rule ('use this only for the short public directory card'), naming the alternative tool directly. Both the positive and negative conditions are spelled out rather than implied.

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