calculate_trading_cost

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety. The description adds context about the calculation nature (shows savings vs standard fees) without contradicting annotations. It provides a useful behavioral hint beyond the structured data, though it doesn't mention potential input validation or error cases.

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 two sentences with no unnecessary words. The first sentence states the core purpose, and the second clarifies the output. Everything earns its place, and the key information is front-loaded.

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 relatively simple calculation tool with no output schema, the description adequately hints at the output (savings vs standard fees) and implies the necessary inputs (exchange, volume, type) through the schema. It does not discuss edge cases or response format, but the schema and annotations fill most gaps. It is nearly complete for an agent to call 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 description coverage is 100%, so every parameter (type, volume, country, exchange) is already described in the schema. The description only reinforces 'trade volume' which is already in the schema, adding no new meaning or clarifying units, formats, or constraints beyond what exists. This meets the baseline for high schema coverage.

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 clearly states the verb 'calculate' and the specific resource (trading cost and savings with CoinRebate referral codes). It also explains the output (savings vs standard fees) and distinguishes itself from siblings like get_exchange_fees by focusing on actual cost with referral codes. The wording is specific and unambiguous.

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 implies usage—when you need to know savings from referral codes for a given volume—but it does not explicitly compare with alternatives such as get_exchange_fees, compare_fees, or get_best_referral. No exclusion guidance is provided, so an agent might not know when to choose this over siblings.

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