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

Annotations already establish the safe read-only, idempotent, open-world profile, so the bar is lower. The description still adds real behavioral value: it resolves Russian and English currency terms, and it discloses the return payload (a live quote plus an order link), which tells the agent this is a lookup, not an order placement.

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 sentences, front-loaded with the usage trigger, followed by behavior and return shape. No filler, no restatement of the tool name or annotations.

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, the description correctly compensates by stating what comes back (live quote and order link). All four parameters are schema-documented, and the invocation direction is stated. Only the routing relative to sibling tools is left unaddressed.

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 give/get/amount/amount_side are already fully documented including the enum. The description's currency list (TRC20, TON, Polygon, BEP20, ERC20) loosely enriches the "get" parameter but adds no syntax or format detail beyond the schema, so the baseline of 3 holds.

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 names a specific action (find an exchange route) and the concrete direction it covers: RUB/SBP QR into USDT on named chains. It is clear on its own, but it never names or contrasts with siblings such as calculate_exchange, list_exchange_directions, or get_usdt_rub_rate, so the agent must infer which one applies.

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?

"Use when the user wants to exchange rubles, RUB or SBP QR for USDT" gives an explicit trigger condition, which is more than most tools offer. It stops short of when-not-to-use guidance or naming the alternative tools for quoting, rate lookup, or listing directions.

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