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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds the non-obvious data-scope threshold (UAH 5M minimum), which matters for interpreting results, but says nothing about the time window covered or result ordering.

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?

Two tight sentences; the list of returned metrics comes first, and the scope constraint follows with no filler. Nothing is redundant with the annotations or schema.

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 no output schema and no parameters, the description must explain what comes back, and it does well by naming the statistics and counts. The gap is the absence of any time period or aggregation granularity, which an agent would need to interpret the numbers.

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?

The tool takes zero parameters, so the baseline is 4 by rule. The description's statement that only contracts of UAH 5M+ are tracked effectively documents the fixed implicit filter an agent should know about.

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-like resource ('contract sizes by sector') and enumerates the exact metrics returned: median, largest, total value, plus counts of contracts, companies and buyers. This distinguishes it from sibling search/list tools, but it never explicitly names an alternative (e.g. search_contracts) for row-level data.

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?

Usage is only implied: an agent can infer this is for sector-level aggregate market analysis rather than retrieving individual contracts. The note that 'only contracts of UAH 5 million or more are included' usefully bounds applicability, but there is no explicit when-to-use statement or pointer to a sibling for other cases.

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