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

Annotations already establish readOnlyHint and idempotentHint, so the safety profile is covered. The description adds genuinely non-structured context: the term is derived from the notice's end date or duration, renewals are excluded from the cutoff, and the follow-on tender is probable but not guaranteed — the last point is important interpretive caveat for an agent.

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?

Three sentences, front-loaded with the resource definition before the caveat and the input requirement. The parenthetical "(end date or duration, without renewals)" is dense but each clause carries meaning; only minor tightening is possible.

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 right thing by naming the returned fields (winner, renewals, offers). The main residual gap is nothing about result volume, ordering or pagination for what could be a long list, but nothing needed to call it correctly is missing.

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%, so 3 is the baseline. The description goes beyond the schema by expressing the disjunctive constraint that at least one of gewerk, land or buyer must be supplied — something the flat optional object schema does not convey — and by clarifying that 'months' measures from today.

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 states a specific resource (awarded service and supply contracts) and a specific filter (term ends within the next months per the notice), plus the fields returned. It does not name a sibling such as search_tenders or get_company_awards to draw the contrast explicitly, so it stops just short of a 5.

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?

"Needs at least gewerk, land or buyer" gives a concrete minimum-input precondition, and "A new tender is likely but not certain" tells the agent how to frame the result. There is no explicit when-not or named alternative, so it is clear context without exclusions.

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