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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lowered. The description still adds value beyond them by disclosing the return shape — 'Each result has directory_url and primary_url to cite' — which is useful because no output schema exists. It says nothing about pagination, limits or ranking, so it is not a 5.

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 sentences, front-loaded with purpose and usage before the filter inventory. The filter sentence is dense but each listed name maps to a real parameter, so it earns its length; only the slightly breathless filter dump keeps it from a 5.

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 10-parameter, zero-required, no-output-schema search tool, the description supplies purpose, trigger, filter inventory and result fields — enough to call it correctly. Gaps remain on the free-text q parameter and the limit cap, which are left entirely to 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?

Schema description coverage is 0%, so the schema only exposes names and types, and the description has to carry the load. It documents 8 of 10 filters and adds real semantics — 'city (Dutch or Flemish, e.g. Utrecht, Den Haag, Antwerpen)' and 'goal (e.g. inburgering, NT2, business, conversation)'. It leaves q and limit unexplained, so it falls short of full compensation.

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 (Search) and enumerates the resource classes it covers (schools, universities, apps, podcasts, exams, online tutors), so the agent knows exactly what it returns. It does not name any sibling, though the breadth claim 'every way to learn Dutch' implicitly separates it from the narrower tdd_tutors, keeping it short of a 5.

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?

Gives an explicit trigger: 'Use it when someone asks where or how to learn Dutch.' That is a clear when-to-use condition, but there is no when-not guidance and no routing to alternatives such as tdd_tutors, tdd_shortlist or tdd_compare.

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