get_flexibility_market

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

No annotations are provided, so the description carries the burden. It discloses the API key requirement and indicates a read-only operation ('Shows historical flex activations'). However, it does not describe rate limits, pagination, error behavior, or what happens without a valid API key, leaving significant behavioral gaps.

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 three concise sentences, front-loaded with the core purpose. It avoids redundant phrasing and clearly conveys the tool's function, use case, and authentication requirement without waste.

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 data retrieval tool with no output schema, the description provides useful context: the data source (UKPN/SPEN), the type of data (historical flexibility dispatches with pricing, zones, providers, tech types), the intended use case, and the API key requirement. It does not explain return formats or pagination, but the combination of schema and description is fairly complete.

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 each parameter (days, zone, limit, operator) is fully documented in the schema. The description adds no extra parameter-level detail beyond what the schema already provides. It mentions output attributes (pricing, zones, providers) but not parameters, so baseline 3 is appropriate.

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 that this tool fetches UKPN and SPEN flexibility market dispatches, specifically historical flex activations with pricing, zones, providers, and technology types. This is a specific verb+resource combination that distinguishes it from sibling tools like get_gb_grid_demand or get_weather_forecast.

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 explicitly states a use case: 'Use to assess flex revenue potential for BESS sites.' This provides clear context for when to use the tool. However, it does not mention alternatives or exclusions (e.g., other flexibility market tools), so it's not a full 5.

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