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

With no annotations, the description carries the full behavioral burden, and it does disclose one important trait: a blackout from 24 to 29 Nov 2026, plus that results shift from forecast to official count after polls close. It says nothing about availability outside the blackout, rate limits, or the shape of the response.

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, front-loaded with the resource and the fields returned, then the temporal caveats. The telegraphic phrasing ('seat order, last seat') is slightly cryptic but no sentence is filler.

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 zero-parameter read tool with no output schema, the description covers subject matter and timing constraints, which is most of what an agent needs. It stops short of explaining what the fields like 'last seat' or 'seat order' actually mean, which matters given there is no output schema to fall back on.

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 takes no parameters, so there is nothing for the description to disambiguate; the zero-parameter baseline applies. The description instead spends its words on describing output content, which is the right use of space here.

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 names a specific resource (Spanish general election 2026, all 52 constituencies) and enumerates the data returned: median seats per list, vote share, seat order and last seat. It is clearly distinct from generic siblings like get_election, though it never explicitly contrasts itself with the closely related get_spain_general_2026 or get_constituency_results.

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?

Usage is only implied by the data described ('after polls close: official count per constituency, forecast for comparison'), which hints at pre- vs post-election use. There is no explicit when-to-use or when-not-to-use guidance and no naming of alternatives such as get_spain_general_2026, leaving the agent to infer routing.

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