Сумма прописью

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

Annotations already declare readOnlyHint=true and openWorldHint=false; the description reinforces the latter with 'Только вычисление, без сети' (calculation only, no network) and discloses output behavior (kopecks as digits by default vs fully in words). It does not need rate-limit/auth detail for a pure offline computation, so 4 rather than 5.

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 output format example and the primary purpose are front-loaded, followed by currency scope, usage, and the offline note. Every sentence carries distinct, non-redundant information and none could be removed without losing value.

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 3-param, no-output-schema computation tool, the description covers input semantics, output format, supported currencies, and routing versus siblings. An agent has everything it needs to call and interpret the tool correctly.

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 coverage is 100%, so the baseline is 3, but the description adds real meaning: it explains currency=none for a plain number without currency and maps minor_in_words to the 'kopecks in digits vs words' behavior with a worked example. This goes beyond the schema's terse field descriptions.

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+resource (converts an amount into text) and immediately shows the exact output format, so the agent knows precisely what it produces. It also distinguishes itself from siblings by noting that invoice_create/act_create already embed this conversion, making it unambiguous versus peers.

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?

Gives explicit when-to-use (contracts, receipts, payment orders) and when-not-to-use (invoices/acts from invoice_create/act_create already contain the amount in words), naming the sibling alternatives directly. Nothing about tool selection is left to inference.

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