search_breach

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

With no annotations, the description carries the full burden and does add real behavioral context: it discloses the HIBP_API_KEY env var requirement, flags the operation as '[passive]', and notes it makes one request to haveibeenpwned.com. It stops short of describing error handling for unknown addresses or rate-limit behavior, but the auth and opsec disclosures are meaningful.

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 fragments, front-loaded with the core purpose, then implementation constraints. Every clause earns its place; the bracketed '[passive]' and provider note are terse but load-bearing. Slightly telegraphic but efficient.

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?

There is no output schema and no annotations, so the description should say more about what a result looks like — breach names, counts, or a bare boolean — and about behavior on a miss. The auth and network context is covered, but the return shape is left entirely unspecified.

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 coverage is 50%: json_output is documented in the schema while email is bare. The description implies the email is the lookup key but adds no format or validation guidance, and says nothing about json_output. Adequate baseline, not compensating for the gap.

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 ('Check if an email appears in data breaches') and names the data source (HaveIBeenPwned), which cleanly separates it from siblings like search_paste or search_ip. An agent can tell immediately this is an email-breach lookup, not a generic search.

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 purpose implies when it applies (you have an email and want breach exposure), but there is no explicit when-to-use guidance, no exclusions, and no mention of alternatives such as search_paste or investigate_multi for broader email pivoting. Usage is inferable rather than stated.

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