EU Open Data Catalogue List

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

Annotations already carry the safety profile (readOnlyHint, idempotentHint, destructiveHint=false), lowering the bar. The description adds genuinely useful context beyond annotations: 'no auth required' and the underlying Hub-Search API source. No contradiction with annotations.

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, zero waste. Purpose, examples, filter capability, data source, and auth are all front-loaded and each clause earns its place.

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?

Output schema exists, annotations carry the safety profile, and both parameters are documented. The ~211 count matches the limit maximum of 211, giving the agent a coherent model of the tool. Nothing needed for correct invocation 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 both parameters are documented in the schema itself. The description reinforces the query parameter with real examples ('geo' matches 'geocat-li', 'gdi-de'), which adds a little value but is largely redundant given the schema descriptions. Baseline 3 is appropriate.

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 ('List'), a precise resource (catalogues feeding the EU Open Data Portal), a count (~211), and concrete example ids ('gdi-de', 'govdata', 'geocat-li'). It clearly differentiates from sibling tools like data-europa.datasets.search and data-europa.reference.theme_list by naming the exact entity type returned.

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?

Describes the optional id-substring filter and gives usage examples for the query parameter, plus states the data source and auth requirement. It does not explicitly name when-not-to-use or route to an alternative reference tool, but the scope ('catalogues', not datasets/themes) makes the use case evident.

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