get_rate

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does state what the tool returns (name and current value), which is helpful. However, it doesn't disclose whether this is a real-time quote, delayed data, cached values, or what happens for invalid symbols. Moderate transparency but not comprehensive.

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 efficient and well-structured: two sentences with the purpose in the first and return value in the second. No wasted words or redundant information. Slightly more could be done but it's appropriately sized for a simple single-parameter 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?

The tool has a single parameter with 100% schema coverage and an output schema exists. For a simple lookup tool, the description provides the essential purpose and return format (name and current value). The output schema handles return value details. Complete enough for the tool's simplicity, though could mention data freshness/caching behavior.

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% with the symbol parameter clearly documented with examples (SELIC, CDI, IPCA). The description mentions 'by its symbol' which reinforces the parameter usage. Baseline 3 is appropriate since the schema already does the heavy lifting, and the description adds minimal additional semantic value beyond confirming the parameter exists.

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 what the tool does: get the current value of an economic rate/index by its symbol. The verb 'Get' with resource 'current value of an economic rate/index' is specific. However, it doesn't explicitly distinguish itself from sibling tools like get_exchange_rate or list_rates, though its symbol-based lookup for rates like SELIC/CDI/IPCA does imply this distinction.

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 context (lookup by symbol) but provides no explicit guidance on when to use this tool versus alternatives like get_exchange_rate or list_rates. There's no when-not-to-use guidance, no mention of situations where this tool is preferred or inappropriate.

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