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

Annotations already declare readOnly/idempotent/openWorld, and the description adds genuinely new operational behavior: the source has no full-text search API, `query` filters client-side on title and published abstract only, the scan covers at most 200 of the most recently modified matching candidates, and the response signals when that scan was partial. These are exactly the quirks an agent cannot infer from structured fields.

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?

Two sentences, front-loaded with the purpose and with no filler; the caveats are packed into the second sentence. Slightly dense and comma-heavy, but essentially every clause carries information the agent needs.

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 an 8-parameter, all-optional search with no output schema, the description covers the crucial behavioral constraints (client-side query cap, partial-scan signalling) and states what is returned (ECLIs resolvable via the getter). Nothing needed to call it correctly 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 100%, so the baseline is 3, but the description adds real semantics the schema does not: `query` is a case-insensitive substring over title/abstract only, is capped at 200 candidates, and may yield partial results. It also clarifies the filter-dimension interplay (court/domain/type/date range) governing the other parameters.

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 resource (Dutch court decisions/uitspraken/conclusies), enumerates the filter dimensions, and explicitly names the sibling it complements: 'Returns ECLIs that nl_rechtspraak_get_decision resolves to the full text.' An agent can distinguish it from the getter without opening either schema.

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 clear context for when the `query` parameter is worth using and warns that it is not a full-text search, which steers the agent away from a misuse. It does not, however, state an explicit alternative tool ('use X when Y') beyond pointing at the getter for resolving ECLIs, so it stops short of full when/when-not routing.

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