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

Annotations already cover read-only, open-world, idempotent, and non-destructive behavior. The description adds specific behavioral details: only active warnings, output attributes, and the implication that expired warnings are excluded (default false). No contradictions with 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?

A single, front-loaded sentence efficiently communicates the tool's purpose and output details without redundancy. The list of warning types and field names is compact and informative.

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 simplicity of the tool, full schema coverage, and the presence of an output schema, the description is complete. It covers the domain, scope, data source, and output attributes, while the schema and annotations handle the remaining operational details.

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 coverage is 100%, with each parameter fully described. The description adds no new parameter-level information beyond what the schema already provides, though it reinforces the 'active' default through the word 'Active'. Baseline 3 applies.

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 'Active FMI weather warnings for Finland' and enumerates specific warning types and output fields (headline, severity, colour, validity, regions). This verb-like noun phrase with detailed scope clearly differentiates it from sibling tools like forecast or observations.

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 usage for retrieving current warning status but does not explicitly name alternatives or provide when-not-to-use guidance. The 'Active' qualifier gives clear context, but there is no direct comparison to siblings.

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