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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower; the description still adds real context by naming the regulatory source, the unit (PLN per litre), and the conditional nature of the next-day price ('if announced'), which tells the agent that field may be absent. It stops short of stating publication cadence or how far back announcements go, which would matter for interpreting the history window.

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 front-loaded sentence carrying the fuels, the unit, the issuing authority and the three content types; no filler or repetition. Every clause contributes information an agent would otherwise have to guess.

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 an output schema present, return-shape explanation is unnecessary, and the description covers source, units and payload contents well for a single-optional-parameter read tool. The remaining gap is the relationship to the near-duplicate sibling get_energy_prices, which any agent selecting between price tools would need.

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% and the single optional parameter already documents default 7 and maximum 60. The phrase 'recent history' in the description loosely mirrors the history parameter but adds no semantics beyond the schema, so the 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 resource — maximum retail prices of Pb95, Pb98 and diesel in PLN per litre — with the authoritative source (Minister of Energy, Monitor Polski). The returned content (current price, next-day price if announced, history) is explicit, so an agent knows exactly what comes back. It does not, however, distinguish itself from the sibling get_energy_prices, which is the most likely source of selection confusion.

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?

The description never says when to call this instead of get_energy_prices, get_dataset or other price-related siblings, nor does it mention prerequisites or exclusions. The only hint is implicit: the mention of 'next day price if announced' signals a forward-looking use case, but the agent must infer that.

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