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

Annotations already provide readOnlyHint and idempotentHint, so the description does not need to restate safety. It adds value by describing the data composition and explaining that 'Active region data helps identify which region is driving current activity,' giving behavioral context beyond the annotation metadata. It does not contradict annotations.

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 compact and front-loaded with the core concept ('Solar flare and radiation storm picture:'), then enumerates specific data points and finishes with the operational significance. There is no redundancy; every sentence contributes to understanding the tool's functionality and relevance.

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 is read-only with one optional parameter and an output schema present, the description effectively covers what data is returned, the purpose, and the use case. It explains the meaning of the data (R-scale, S-scale, active regions) sufficiently for an agent to decide when to invoke it. Nothing essential is missing.

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 input schema has 100% description coverage, documenting the include_regions parameter with its default and purpose. The description mentions active region data but does not directly explain the parameter, so it adds minimal extra meaning beyond what the schema already provides. Baseline of 3 is appropriate given full schema coverage.

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 the tool provides a 'Solar flare and radiation storm picture' with specific data elements (GOES X-ray flux, flare-class probabilities, active regions, proton flux). It identifies the resource and content uniquely, but does not explicitly distinguish it from sibling tools like get_alerts or get_conditions, though the described data is clearly distinct.

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 explicit context for when to use it: 'For operators tracking HF radio blackout (R-scale, driven by X-ray) and radiation storm risk (S-scale, driven by protons).' This clarifies the intended use case and target audience, though it does not mention alternatives or when not to use other tools.

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