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

No annotations exist, so the description carries the full burden of disclosing behavior. It discloses nothing: no external API calls, no breach-check semantics, no return behavior, no limitations. The text is a pure tautology with no behavioral content.

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 extremely short, but this is under-specification rather than conciseness. It contains only a repeated name and provides no front-loaded actionable information. Every opportunity to add value is 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?

With no annotations, no output schema, and a two-sentence description that says nothing, the tool is completely inadequate. An agent cannot know what to pass, what to expect, or whether it is even the right tool. The definition is effectively useless.

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 schema provides descriptions for both parameters ('Email to process', 'Account to process'), so coverage is 100%. However, these descriptions add almost no meaning — they only echo the parameter names. The description adds nothing beyond this, and the semantics of how 'email' and 'account' relate (e.g., which is required, what happens if both are given) remain unclear.

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 is 'Haveibeenpwned: Haveibeenpwned', which merely repeats the tool name. It states no verb, resource, or action — an agent cannot determine what this tool does. The sibling list contains many similarly named tools, and nothing distinguishes this one.

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?

There is zero guidance on when to use this tool versus alternatives. No mention of when to prefer x402-haveibeenpwned over sibling tools like x402-password-leak or x402-email-verify. An agent is left guessing from the name alone.

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