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

Annotations declare readOnlyHint and openWorldHint, so the safety profile is already established. The description adds substantial behavioral context: KRW conversion via FRED DEXKOUS, supported quote handling, premium formula, return structure, geo-blocking caveat, and error behavior for unknown symbols and missing FRED keys.

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 organized into clear sections — summary, Args, Returns, Examples, Errors — and every sentence earns its place. The core use case is front-loaded, and the examples and error notes are compact and directly actionable.

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?

The tool is complex with 5 optional parameters, output schema, and notable caveats, and the description covers all of it: parameter defaults, supported values, conversion method, return fields, formula, example mappings, and error handling. Nothing an agent needs to call it correctly is missing.

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 goes well beyond the schema. It explains the role of each leg, default pairings, how quote currencies are treated, and gives concrete examples that map natural language to parameter values. It also documents error conditions tied to parameter choices.

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 states a clear verb and resource: compare crypto asset prices across two exchanges, convert both legs to USD, and report premium. It differentiates itself from sibling tools by explicitly naming get_crypto_ticker and get_crypto_ohlcv as non-fit alternatives.

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 gives explicit when-to-use guidance with the kimchi premium example and maps natural-language phrases to concrete argument sets. It also states exclusions: 'Don't use for a single price (get_crypto_ticker) or history (get_crypto_ohlcv).' This fully routes the agent.

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