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

Annotations already provide readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds useful behavioral context beyond that: the operation produces a comparison table for client responses and is limited to 2–4 machines. It does not detail errors or edge cases, but this is a minor gap given the read-only nature.

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 compact and front-loaded: it leads with the core purpose, then covers input variants and output format in two clear sentences. There is no filler, repetition of annotations, or unnecessary detail.

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 the read-only, idempotent annotations, full schema coverage, and presence of an output schema, the description is complete enough for correct invocation. It specifies the input variants, the supported machine count, the compared fields, and the expected output form (a table for the client). Nothing essential for selecting or calling the tool is missing.

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 input schema already covers 100% of parameter descriptions, but the description adds meaningful constraints not present in the schema: the tool compares 2–4 machines, and 'ids' is an alternative to 'id_a/id_b'. The concrete example with product numbers further helps invocation, so the description adds value beyond the raw schema.

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 states a specific verb ('Сравнение' / compare) and a precise resource: 2–4 factory machines by technical characteristics and price. It lists the compared fields (working field, spindle, price, availability, description), which makes the tool's purpose unmistakable and clearly differentiates it from sibling tools like get_machine_detail or search_machines.

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 clearly implies when to use the tool: when a client needs a comparison of 2–4 machines and a tabular answer. It does not explicitly name alternatives or state 'when not to use', so it misses the top level of guidance, but the context is clear enough for an agent to select it appropriately.

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