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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds the temporal scope (today's performance) but does not disclose output behavior such as aggregation by sectors, sorting by |change|, or the effect of optional parameters. Since annotations lower the burden, a middle score is appropriate.

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?

The description is a single efficient sentence with no filler, front-loading the key subject (GPW sectors) and the core question (better vs worse today). It is somewhat sparse, but this dimension rewards conciseness and the sentence earns its place.

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?

The description gives enough to understand the basic call: a read-only sector pulse for the Polish market. However, there is no output schema and the description does not explain return shape, sector filtering rules, or market-context options; the detailed parameter schema partially compensates for this.

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 tool description itself adds no parameter-level meaning, but the schema already documents universe, topMoversPerSector, minSymbolsPerSector, and includeMarketContext thoroughly, including defaults and max values.

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 clearly identifies the resource: GPW sector performance, and the intent: comparing which sectors are doing better or worse today. It lacks an explicit operation verb like 'get' or 'aggregate', and it does not explicitly distinguish itself from siblings, so it does not earn 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?

There is no guidance on when to use this tool versus alternatives, no exclusions, and no mention of related sibling tools. The phrase 'dziś' implies a daily snapshot use case, but that is not developed into actionable selection guidance.

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