breachDataClasses

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

With no annotations, the description carries the behavioral disclosure burden. It reveals that the endpoint is free and requires no API key, which is useful. However, it does not mention rate limits, response format, or pagination, leaving some behavioral uncertainty.

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 description is only two sentences, with the main action front-loaded. Every phrase adds value, including the clarification of 'data classes' and the free/no-API-key note. No words are wasted.

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 zero-parameter tool, the description provides sufficient context: what it lists, where the data comes from, and access requirements. It even defines the ambiguous term. No output schema exists, but the phrase 'List all data classes' implies a list result, which is enough.

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?

The tool has zero parameters, so the baseline for parameter semantics is 4. The description does not need to explain parameters, and it adds no parameter-specific information, which is appropriate here.

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 uses the specific verb 'List' with a clear resource ('all data classes') and context ('known to HaveIBeenPwned'). It also clarifies the term with a parenthetical definition, making the purpose unmistakable and distinct from sibling breach-related tools.

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?

The description clearly states what the tool does and notes that it is free and requires no API key, which guides usage. It does not explicitly mention alternatives or exclusions, but the use case is unambiguous given the tool's specific purpose.

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