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

The readOnlyHint annotation already covers the safety profile, so the bar for the description is lower. The description adds useful context with 'candidates only', indicating the results are non-authoritative suggestions, but it does not describe output shape, ordering, or how the taxonomy relation is computed. 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?

The description is compact and mostly information-dense, front-loading the core purpose. The trailing 'hint.' is cryptic and slightly undermines clarity, but overall the description avoids unnecessary words.

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 simple read-only lookup tool, the description covers the core input and purpose. However, with no output schema, the absence of any description of the return shape or candidate format is a noticeable gap, even though 'candidates only' gives a partial hint.

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%, so parameter semantics are already well documented in the schema. The description restates the ELI-or-SR entry options but adds little beyond what the schema descriptions already provide.

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 identifies the action: find acts in the same field of law via the legal taxonomy, using ELI or SR as entry points. It is specific about the resource and operation, though it does not explicitly differentiate itself from similar taxonomy-related sibling tools like fedlex.explore_node or fedlex.get_taxonomy.

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?

It includes an explicit use directive ('use to discover neighbouring Erlasse'), which conveys intent, but it gives no when-not-to-use guidance or named alternatives among the many fedlex siblings. The routing decision is left mostly to inference.

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