get_spain_hourly_prices

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

The description fully discloses behavior and output: it returns a JSON string with hourly prices, stats, and cheapest/most expensive hours. As a read-only query, the 'Get' verb indicates no side effects, and no annotations exist to contradict. The description carries the full burden well.

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 well-organized with sections (Args, Returns, Example) and is concise yet informative. Every sentence adds value, 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?

Given the tool's simplicity (one parameter, clear purpose, and existing output schema), the description covers all necessary details: what the tool returns, the parameter format, and a usage example. It is complete for an agent to invoke 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?

The single parameter 'date' has its format ('YYYY-MM-DD') and an example provided in the description. With 0% schema coverage, the description fully compensates by explaining what the parameter expects.

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 it gets Spanish hourly electricity prices for a specific day, naming the market (OMIE/MIBEL). It distinguishes itself as the simplified Spain-focused version, differentiating from siblings like get_price_analysis or get_generation_mix.

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 clear usage context ('perfect for checking daily electricity costs') and implies it's for Spain-specific spot prices. However, it does not explicitly state when not to use it or mention alternative tools.

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