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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so safety is covered. The description adds real behavioral context the annotations cannot: the thresholds are time-bound (valid 2026-01-01 to 2027-12-31 per Delegierte VO (EU) 2025/2152), change every two years, and prior values are outdated, plus an explanation of schwelle_alt_eur and schwelle_hinweis. No auth/pagination info, but none is relevant for a pure lookup.

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 core answer is front-loaded, then it adds validity context, output fields, and example questions. It is information-dense and most sentences earn their place, though the legal-citation and output-field enumeration edge toward verbosity for a read-only lookup.

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 fully compensates by enumerating key return fields (oberschwellig, schwelle_eur, regime, rechtsgrundlage, gueltigkeit, schwelle_alt_eur, schwelle_hinweis) and the legal basis. Combined with complete param documentation and annotations, an agent has everything needed to call and interpret it.

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 wert, auftraggeber, and leistungsart thoroughly (including enum meanings and German number formatting). The description's additional value is limited to noting the leistungsart value alignment/alias with verfahrenswahl_ermitteln, which is marginal beyond the schema, so the baseline 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?

States a specific verb+resource (checks the current EU procurement threshold) and precisely scopes the deliverable: above/below threshold, the applicable regime, and sub-threshold limits. It also distinguishes itself from the sibling verfahrenswahl_ermitteln by noting that procedure types are determined there, so an agent can tell the two apart without opening schemas.

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?

Explicitly names the use case (does a contract require EU-wide publication or stay within national sub-threshold rules) and backs it with several example user questions. It clarifies its boundary against verfahrenswahl_ermitteln, but does not state any when-not-to-use conditions or other alternatives, so it stops 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.