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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds valuable context about data source (land registry, realised sales) and a key output feature (% difference vs. most expensive), which goes beyond annotations. No contradictions exist.

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 well-structured, with the core purpose front-loaded, followed by keywords. It is bilingual, which adds length but also serves multi-language users. There is some redundancy between the CZ and EN versions and keyword lists, but the essential information is concise and clear.

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?

Given no output schema, the description should explain the full return format. It mentions the % difference but does not detail the overall output structure (e.g., whether it returns a table, individual prices, or just comparisons). The tool is simple, but for an agent to fully understand the response, more detail on output format would be beneficial.

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 both parameters (lokality and jazyk) are already documented in the schema. The description does not add extra parameter-level detail beyond the schema, so it remains at the baseline of 3. Keywords like 'price per m²' are general context, not parameter semantics.

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 states the tool's purpose: comparing apartment prices across 2–8 Prague localities using realised sales from the Czech land registry, and including a percentage difference vs. the most expensive locality. This distinguishes it from siblings like ceny_bytu_lokalita (single locality) and top_ctvrti_praha (ranking), making its unique function explicit.

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 implies usage for multi-locality comparisons but does not explicitly state when to prefer it over alternatives or mention exclusions. It does not reference sibling tools or provide explicit guidance on selecting this tool vs. others, leaving the agent to infer from the tool's specific function.

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