search_eu_implementations

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the safety profile is clear. The description adds useful behavioral context beyond the annotations: it states the database size (1,008 documents), what is returned (EU document metadata with Dutch implementation counts), and the available filtering dimensions. This provides a fuller picture of the tool's behavior.

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 three sentences long, front-loaded with the main action, and every sentence earns its place: the first states what the tool does, the second describes the output and filter capabilities, and the third gives the usage context. No redundant or irrelevant information.

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?

Despite no output schema, the description sufficiently explains what is returned ('EU document metadata with Dutch implementation counts') and the context for use. For a search tool with read-only annotations, this is complete: it covers purpose, output, and usage without needing to enumerate every parameter detail, which the schema handles.

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% with each parameter having a description, which sets a baseline of 3. The description enhances this by summarizing the key filter groups ('type (directive/regulation), year range, community (EU/EG/EEG), and whether a Dutch implementation exists'), giving the agent a quick understanding of how the parameters combine to filter results. This adds value beyond the raw 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?

The description clearly states the tool's function with a specific verb and resource: 'Search EU directives and regulations in the database.' It also distinguishes from siblings by noting 'Use when browsing EU instruments rather than looking up a specific one,' which separates it from lookup-style tools like get_eu_basis or get_provision.

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 explicit usage guidance with both a positive directive ('Use when browsing EU instruments') and a negative one ('rather than looking up a specific one'). Although it does not name a specific alternative tool, the contrast with lookup behavior is clear enough for an agent to decide when to choose this tool.

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