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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety bar is covered. The description adds genuinely useful non-obvious behavior: colour families are collapsed ('a basic colour counts its whole family'), ultrawide is nested inside landscape, pages are short and return a curatorial capsule, and flash/epilepsy questions trigger a special abrupt-light-event result set.

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 dense sentences front-load the scope and facet list, then cover return shape and the special flash query. Efficient with no filler, though the facet enumeration is packed tightly enough to be slightly list-like.

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 16-parameter, zero-required search tool with no output schema, the description covers scope, filterable dimensions, return shape ('a short page brings each work's curatorial capsule'), and one non-obvious query mode. Nothing essential to calling 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?

At 63% schema coverage across 16 params, the description has to compensate and largely does: it names nearly every filterable dimension (colour semantics, loop length, rotation, availability, orientation hierarchy) and clarifies behaviour the schema does not, such as colour family grouping and ultrawide inclusion. It still leaves a few parameters (limit/order/sort_by nuances) to the schema.

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 (the catalogue of 296 moving-image works by César Yagüe) and then enumerates the exact facets that make this a search tool — free text, collection, resolution, orientation, colour, price, year, loop length, rotation, availability. An agent can distinguish this from get_artwork (single fetch), browse_collections (collection taxonomy), and catalog_overview without opening a 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?

Usage is only implied: the enumeration of queryable facets tells the agent this is the retrieval tool for filtered/free-text queries, and the flash/epilepsy sentence hints at a special query mode. But it never explicitly says when to prefer this over browse_collections or get_artwork, and gives no exclusions or prerequisites.

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