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

With no annotations, the description carries the full behavioral burden and meets it well. It discloses grouping behavior, the registration-vs-corporate-family distinction, the output shape (breakdown plus certificates), and the conditional tracker_url field. This is substantive context beyond what the schema provides.

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?

Four sentences, each adding distinct value: scope, a concrete spelling-variant example, output contents, a key caveat, and the tracker_url detail. It is dense rather than padded, though slightly long for a tool description.

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 two-parameter query tool with no output schema, the description is close to complete: it covers return contents, grouping behavior, and a special output field. The only meaningful gap is the meaning and effect of the 'limit' parameter, though its numeric bounds are present in the schema.

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 already describes 'vendor' as 'Vendor name or part of one', and the description adds useful grouping semantics for it. However, 'limit' has no schema description and the description never mentions pagination or result limits, leaving half of the parameters only partially explained.

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 opens with 'Everything one company holds' and specifies NIST spelling-variant grouping, then lists return contents: a breakdown by status and standard plus the certificates themselves. This clearly identifies fips_vendor as the company-level aggregation tool and differentiates it from sibling cert/search 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?

It states the intended query context ('Everything one company holds') and gives an explicit when-not: 'this groups spellings of one registration, not corporate families,' with the nCipher/Thales/Entrust example. It does not explicitly name a sibling alternative, so it stops short of full routing guidance.

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