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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds genuinely new behavior: the returned price is 'real calculated' but is a 'base price before account perks', which warns the agent the final charge may differ. It stops short of saying whether a quote expires or that it does not reserve anything.

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?

Three short sentences, front-loaded with the core action and outputs, then the follow-up action, then the key pricing caveat. No filler or redundant restatement of the 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?

An output schema exists, so return values need not be described, and the pricing caveat is a useful addition. But for a 7-parameter quoting tool with 43% schema coverage, the description leaves the caller guessing about rank, edition, currency, and quantity, and says nothing about quote validity or whether the quote reserves inventory.

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 only 43% (game, server, service documented; rank, edition, currency, quantity undocumented). The description compensates for none of this — it never mentions quantity limits, currency choice, rank, or the Java/Bedrock edition enum. With low coverage the description was obligated to add meaning and does not.

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 and resource: 'Get a real calculated session price and bookUrl for a selected service', and names the two outputs. It is clearly distinguishable from list_services/get_availability, but it never explicitly contrasts itself with those siblings (e.g., 'use get_availability to see slots, get_quote to price one').

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?

Implies the usage flow via 'Share bookUrl to review options and pay on Duoly', which tells the agent what to do with the result. However, it gives no explicit when-to-use vs get_availability or find_session, and no stated preconditions (that game/service ids must come from list_games/list_services).

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