breachSearch

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful behavioral context beyond annotations: the authentication requirement and that this is a paid endpoint, which affects whether an agent should invoke it.

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 tight sentences with the core purpose front-loaded ahead of the auth prerequisite. No wasted words, though it is very brief and could have used the space to differentiate from siblings.

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?

For a simple read-only search tool with a fully documented 3-parameter schema and no output schema, the description covers purpose, resource scope, and auth requirement adequately. Minor gap is the absence of explicit sibling differentiation within the breach tool family.

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%, so the schema fully documents all three parameters (account, truncateResponse, includeUnverified) with defaults. The description's '(email or username)' merely restates what the schema already states, adding no syntax or format detail beyond structured fields.

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 ('Search'), resource ('all data breaches'), and scope ('for a specific account (email or username)'), which clearly differentiates it from list-oriented siblings like breachList/breachLatest. However, it does not explicitly name or contrast with the closely related siblings breachPassword and breachPastes, leaving some ambiguity within the breach family.

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 discloses a meaningful prerequisite ('Requires HIBP_API_KEY (paid endpoint)'), which implies the usage context, but gives no explicit when-to-use vs. when-not guidance or named alternatives such as breachPastes or breachPassword. Usage is implied rather than stated.

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