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

Annotations already declare readOnly, idempotent, closed-world, so safety is covered; the description goes further by disclosing what comes back (data points plus a whole-history summary with min/max price and date, and year-over-year change), the default window, and the important caveat that prices are nominal in contemporaneous złoty with no inflation adjustment. What it omits is behavior on unknown commodities or out-of-range dates.

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, then coverage, then return shape, then the nominal-price caveat. Dense parenthetical enumeration but every clause carries information; nothing is filler.

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 three-parameter read-only query tool with no output schema and full schema coverage, the description supplies what the schema cannot: series start dates per commodity, default window length in both monthly and weekly units, return contents, and the no-inflation-adjustment caveat. Only error/empty-result behavior and the full commodity vocabulary are missing, and the schema supplies examples.

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 the baseline is 3. The description does add real meaning on top of the schema: it explains that the default is the last 36 months or 52 weeks, and it constrains co_tydzien far more sharply than the schema by stating weekly data exists only for consumption wheat and dry maize from 2022, and it implies which commodities have long enough history for the 'od' parameter.

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 names a specific resource and verb: the historical price series for Polish agricultural commodities, with per-commodity coverage windows (grain monthly since 2006, raw milk since 2004, diesel and bread since 2010, US wheat/maize last 24 months). An agent can tell this is the history endpoint. It never names the sibling ceny_aktualne, so the boundary with current-price lookup is left implicit.

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?

'Jak zmieniała się cena' plus the explicit time coverage implies this is the tool for trend/back-history questions, but the description never states when to prefer it over ceny_aktualne or what to do if the commodity has no history. Weekly mode eligibility (only consumption wheat and dry maize, from 2022) is the one usage constraint that is spelled out.

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