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

Annotations already declare readOnly, idempotent and closed-world, so the safety profile is covered. The description usefully adds behavioral context unavailable in structured fields: the result carries calculation steps, the judge's discretion under Article 1022, and the two-tariff comparison for partly non-monetary claims. It stops short of noting error behavior for invalid dates or court types.

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 dense, front-loaded sentences: the first defines the computation and its outputs, the second defines the explanation content and the intended use. No filler, though the parenthetical enumeration of output components is slightly list-heavy.

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 does the work of describing the return payload (amounts plus explanation), which is the key gap it needed to fill; parameter documentation is complete via the schema. Minor omissions remain: no stated error behavior, and no routing guidance against the two sibling lookup tools.

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 the schema already documents date, amount, locale, court_type and no_monetary_value thoroughly, including enum meanings. The description adds only the framing that indexing follows the given date; it does not extend parameter meaning beyond the schema, so the baseline of 3 applies.

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 and resource ("Calculates the Belgian procedural indemnity") and enumerates the concrete outputs (minimum, base, maximum in EUR, indexed for a given date). The purpose is unmistakable. It does not, however, contrast itself with the sibling tools (get_rate_table, get_indexation_status), so an agent must infer that this one computes rather than just returns tariff/index data.

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?

"Use it to explain how and why the amount was reached" gives a purpose for the explanation output but no when-to-use vs. when-not guidance, no prerequisites, and no mention of the sibling tools for raw tariff or index lookups. Usage is implied rather than spelled out.

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