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

No annotations are present, so the description carries the disclosure burden. It conveys the key behavioral output: the latest value, severity level, and 24-hour maximum. It does not describe update frequency or potential observation delay, but for a simple zero-parameter read the core behavior is clear.

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 a single compact sentence with no filler. It front-loads the resource name and directly enumerates the useful output fields.

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 tool with no output schema, the description fully covers what an agent needs to understand the return value: latest Kp value, severity level, and the 24-hour observed maximum. No additional context is necessary to call this tool 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 tool has zero parameters, so there is no parameter meaning for the description to add. The baseline of 4 applies because no parameter documentation is needed.

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 identifies the resource ('current planetary Kp index') and the exact returned content: latest value, level category, and observed 24-hour maximum. The word 'current' and 'observed' distinguish it from the forecast-oriented sibling get_kp_forecast_3day.

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 that this is for accessing the current measured Kp index rather than forecasts, and the observed 24-hour max clarifies the temporal scope. It does not explicitly state exclusions or name alternative tools, but the current-vs-forecast contrast provides clear context.

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