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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description still adds high-value behavior: case-insensitive substring semantics, per-day fetch newest-first, a hard 7-day scan ceiling, and early stop on reaching limit — meaning results can be incomplete. It also discloses the shape of the return (buyer, order type, CPV, deadline, URL).

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?

One dense paragraph with no filler, front-loaded on what is searched and where, then query guidance, then return shape. It is slightly run-on (platform/publisher parenthetical stacked before the core behavior), but every clause carries information.

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?

Despite having no output schema, the description names the returned fields and the URL, explains the limit/date interaction and the 7-day scan bound, and the read-only annotations close the safety question. An agent has what it needs to call this correctly and interpret partial results.

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 four parameters are already documented with defaults and formats; baseline 3 applies. The description reinforces keyword/CPV matching and the publish-date window but adds no syntax or edge-case meaning beyond the schema.

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 ('keyword search') and a precisely bounded resource (Polish public procurement notices in the Biuletyn Zamówień Publicznych via e-Zamówienia), and enumerates the three fields matched plus the publish-date window. It does not explicitly contrast itself with the sibling pl_tender_recent or pl_tender_by_buyer, so the differentiation is only implicit in the word 'keyword'.

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?

Gives concrete query-formulation guidance ('use POLISH keywords for best recall', sample terms, CPV prefixes), which is real usage help. However it never states when to pick this over pl_tender_recent or pl_tender_by_buyer; the agent must infer that a keyword query is the differentiator.

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