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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds real behavioral value beyond that: it discloses the return shape (effective end date plus per-step legal reasoning for each reduction), the normalization rule, and the legal basis with a currency date (Stand 2026-07-14). It stops short of noting anything about edge cases or invalid inputs.

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?

Front-loaded with the core purpose before the legal citations and examples. The five example questions are somewhat verbose but serve retrieval and routing, so they earn their place. Minor redundancy in the legal-scope sentence.

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 correctly explains what is returned (end date plus per-step reasoning) and enumerates the covered frameworks and reductions. Nothing essential to correct invocation is missing for a read-only calculation tool.

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 all six parameters including the reduction flags and enum meanings are already documented in the schema. The description restates the reduction factors (electronic, prior notice, urgency) at a high level but adds no syntax or interaction detail the schema lacks. Baseline 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?

Names a specific verb+resource (returns the effective end date for submission/participation deadlines) and states the legal scope (VgV, VOB/A Abschnitt 2 EU) plus the computation rule (shift to next working day per VO 1182/71). It explicitly distinguishes itself from the sibling vergabe_wartefrist, which handles the § 134 GWB standstill period.

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?

States the exact class of question it answers ('which date a submission deadline falls' or 'whether the minimum period can be shortened') and names the alternative tool for a different deadline type. The listed example questions reinforce when to reach for it.

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