count_tenders

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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so safety is covered. The description adds real behavioral value beyond that: it returns a count rather than a list, it is cheap to call, and scope defaults to ALL so date ranges span the archive. Return shape is covered by the output schema, so nothing critical is missing.

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-loads the core purpose in the first clause, then adds filter routing and a usage tip in two short sentences. The parenthetical and tip both earn their place, though the tip is slightly advisory rather than definitional.

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 7-parameter count tool with an output schema and full annotation coverage, the description supplies the key non-obvious facts: no listing, cheap, scope default ALL. The main residual gap is parameter-level detail, which it offloads to a sibling rather than stating outright.

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 0%, so the description must carry the parameter burden. It explains the scope default and its effect ('ALL so date ranges count the archive') and delegates the rest to search_tenders' filter set, which is a useful pointer but not a substitute for documenting keywords, countries, cpv_codes, notice_types, and the published_since/until format.

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 ('count matching notices') and immediately distinguishes it from the listing behavior of its sibling by saying 'without listing them'. The parenthetical '(cheap demand signal)' clarifies the intent behind the tool, so an agent understands both what it does and why it exists versus search_tenders.

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 routes the agent to search_tenders for the filter set ('Same filters as search_tenders') and gives a concrete usage pattern (compare the same filters across two date windows). It lacks an explicit when-not clause (e.g., 'do not use when you need the actual notices'), but the context is clear.

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