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

Beyond the readOnly/idempotent/openWorld annotations, the description discloses the result shape (up to 25 marks, similarity tier, filing registers) and an important data-freshness trait: EU marks are live from EUIPO but other registers come from a refreshed copy where recent filings can be missing. It also sets expectations that results are a screen rather than clearance.

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 sentences with the scope first, the return content second, and the caveat last. Every sentence earns its place and nothing is padded.

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 output schema, the description supplies the return semantics (what the marks include, how many, and which registers) plus the freshness limitation. For a one-parameter read-only screen, nothing an agent needs in order to call and interpret it is missing.

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 0% and the single `mark` parameter has no schema description, so the description must carry the meaning. It does by establishing that exactly one brand name is screened (not a batch), though it says nothing about expected format or normalization of the name.

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 ("Screens one brand name against trademark registers") and pins the scope to a single name rather than a list. It is clear on its own but never names a sibling such as check_names or run_investigation, so an agent must infer how it differs from the other screening 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?

"No account needed" and "It is a screen, not clearance" give a clear context and a hard usage boundary, which is exactly the kind of framing an agent needs before presenting results to a user. However, no alternative tool is named and no explicit when-not conditions beyond the clearance caveat are given.

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