compare_total_cost

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safe, offline-computation profile is established. The description adds the scope of what gets combined and the required-vs-optional split, but discloses no failure/fallback behavior, no output ranking semantics, and no rate or auth considerations. With annotations carrying the safety burden, this is adequate but not rich.

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 when-to-use condition is front-loaded, which is good. However the content is duplicated verbatim in Chinese and English, roughly doubling length with no new information per reader, and the sentence "This is the most comprehensive comparison tool" is unsupported boilerplate that does not earn its place.

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 25-parameter tool with no output schema, the description covers the trigger, the three required inputs, and the optional families that change the result, which is enough to call it correctly. What is missing is any statement of what the ranked result contains or how the "best exchange" ranking is produced, which an agent presenting results would benefit from.

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% across all 25 params, so the schema already documents syntax, defaults, enums, and edge behavior. The description only gestures at a handful of them (holdingHours, useToken, fiat amounts, withdrawal details) without adding format or interpretation detail beyond the schema. Baseline 3 is correct.

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 (compare total cost across exchanges) and enumerates the exact cost components folded in: trading fees, funding rates, withdrawal fees, spread, and optional fiat on/off-ramp fees. That enumeration implicitly separates it from narrower siblings (compare_exchange_fees, get_withdrawal_fees), though it never names an alternative and instead asserts "most comprehensive" as a self-claim rather than a differentiation.

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 a clear triggering condition ("当用户要求比较不同交易所的真实总成本...时使用") and lists the prerequisites (purpose, country, monthly volume) plus optional inputs. It stops short of the 5 bar because it names no exclusions and no sibling alternative to route away to when only a partial cost comparison is wanted.

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