Cheap / low-carbon hours ahead (Finland)

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

With no annotations, the description carries the full burden and does well: it discloses the computation method (residual load from Fingrid consumption, wind and solar forecasts), the direction of the ranking (lower = cleaner/cheaper), and the key caveat that no exchange prices are used. It omits return shape/pagination details, but the methodological disclosure is the substantive risk an agent needs.

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?

Three short sentences, zero filler, with the core ranking semantics front-loaded and the caveat trailing. Every sentence adds information the agent cannot get from the empty parameter schema.

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 conceptual model is complete, but for a tool with no annotations, no output schema, and two completely undocumented parameters, the description should at minimum clarify what topN and hoursAhead control and what the ranked result looks like. As written, an agent can grasp the idea but must guess at invocation semantics.

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 0% – neither topN nor hoursAhead has any description, no defaults or max ranges are explained in prose. The description's 'coming hours' loosely implies hoursAhead but says nothing about topN (how many ranked hours are returned) or the 1-24 / 1-72 bounds, so it fails to compensate for the coverage gap.

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?

States a concrete verb+resource ('Ranks the coming hours by residual load') and defines the metric precisely (consumption forecast minus wind and solar, all Fingrid). It implicitly separates itself from siblings like fingrid_co2_intensity and price tools via 'NOT a price forecast', but never explicitly names an alternative.

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 says what the ranking means and warns it is a heuristic rather than a price forecast, which implies when it is appropriate. However it gives no explicit when-to-use guidance and does not route the agent to fingrid_co2_intensity, fingrid_series, or fmi_fingrid_nowcast for the underlying data.

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