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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description usefully adds the authentication prerequisite ('Requires the organization API key'), which is context the annotations do not provide. It stops short of describing result shape, ordering, or whether obligations are computed or stored.

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 short sentences, front-loaded with what the tool returns, then the access requirement. Nothing is redundant or 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 carries the return-value burden and does so in outline (record, tier, obligations). Combined with the auth note and a fully documented single parameter, an agent has enough to invoke it correctly; only the relationship to the sibling AI Act tools remains unstated.

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% and the single parameter is documented as 'One system; omit for all', so the description has little left to explain. It adds no format or semantics beyond that, which is acceptable at this coverage level but not value-adding.

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?

The description states a specific resource (EU AI Act register) and what it contains: each AI system's current record, tier and applicable obligations. That is clearly a retrieval operation, not a write. It does not, however, distinguish itself from ai_act_check or ai_act_export, which an agent could easily confuse with it.

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?

There is no when-to-use guidance and no mention of alternatives such as ai_act_check (assessment) or ai_act_export (export). The only scoping hint ('omit for all') lives in the schema, not the description, so the agent gets no routing logic here.

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