market_coingecko_exchange_rates

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states what the tool does (getting exchange rates) but does not disclose whether this is a read-only operation, how data is returned, whether pagination or limits apply, or any freshness/availability characteristics. For a tool lacking annotations, this is a significant transparency gap.

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 a single, concise sentence that conveys the essential information without any filler. It is front-loaded and easy to parse, making it an ideal length for a simple, parameterless tool.

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?

Given the tool's low complexity (zero parameters, no nested objects), the description is sufficient for an agent to understand its purpose and invoke it correctly. The lack of an output schema is acceptable for a tool that returns a straightforward list of exchange rates. The description could arguably mention the output format, but for a simple data retrieval tool, this is not a critical gap.

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?

The tool has zero parameters, so there is nothing to explain about input semantics. The description adds meaning by specifying the base currency (BTC) and the scope ('all supported currencies'), which are not captured in the empty schema. This aligns with the baseline expectation for parameterless tools.

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 tool's function: retrieving BTC exchange rates against all supported currencies. The verb 'Get' and resource 'BTC exchange rates' are specific, and the scope is well-defined. While it doesn't explicitly distinguish from similar market tools like market_coingecko_simple_price, the phrase 'all supported currencies' differentiates it enough for common understanding.

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 when to use this tool (when you need BTC exchange rates for all supported currencies), but it provides no explicit guidance on alternatives or exclusions. The simple, zero-parameter interface reduces the need for detailed usage instructions, but the description does not mention when other rate tools would be more appropriate.

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