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

Annotations already establish read-only, open-world, idempotent, and non-destructive behavior. The description adds useful context by defining the scope (EMA and national authorities), the urgency of DHPCs, and exactly what fields are returned. It does not discuss rate limits or coverage caveats, but the annotation profile lowers that burden.

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?

The description is front-loaded with a definition, then output fields, then example queries; each sentence contributes useful information. The opening is slightly wordy but remains efficient for a domain-specific tool.

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 read-only tool with zero required parameters and a fully documented schema, the description plus schema covers invocation and return contents well. There is no output schema, but the description enumerates the key returned fields, and openWorldHint signals potential data completeness caveats.

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 100%, with all five optional parameters documented including examples. The description itself adds no parameter-level detail beyond the schema, so the baseline score of 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?

The description clearly defines DHPCs as EU-wide safety communications and lists the specific outputs returned: medicine, active substance(s), DHPC type, regulatory outcome, dissemination date, and document URL. It also provides natural-language example questions, making it easy to distinguish from the other EMA-related siblings.

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?

The description gives concrete answer patterns such as 'what safety communications has the EMA issued about X' and 'has there been a DHPC for semaglutide', which clearly signals when to invoke the tool. It does not explicitly name sibling alternatives or state when not to use it, so it falls slightly short of a 5.

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