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

The description goes well beyond the readOnlyHint/idempotentHint annotations by detailing what alerts contain (event type, awareness level, severity, certainty, counties, description, consequences, valid time interval), available filters, language options, licensing, and the fact that no auth or upstream cost is involved. This enriches the agent's model of what to expect. 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?

The description is a dense but purposeful paragraph. Each clause conveys operational value (scope, event coverage, alert fields, filters, languages, licensing/auth). No redundant statements; main purpose front-loaded.

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 read-only lookup tool with output schema, the description covers what's needed: scope, filters, language, and cost/auth traits. It doesn't address defaults or pagination, but these are minor for a 3-optional-param tool with 0 required parameters and an output schema. Complete enough for an agent to call 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?

Schema coverage is 100% and each parameter already has descriptions with examples. The description reinforces the filter options ('Filter by event type slug ... or by county name') and lists the allowed event slugs, but it doesn't add new semantic detail beyond the schema. 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?

States a specific verb ('Get all active weather alerts') with a clear resource and geographic scope ('Norwegian Meteorological Institute for Norway'). Distinguishes from siblings like metno.weather.forecast and metno.weather.nowcast by focusing on alerts, and from other alert tools by the Norway scope.

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 makes the use case clear: retrieve current active alerts for Norway, optionally filtered by event type or county. It doesn't explicitly name alternatives or exclusion conditions, but the Norway-specific scope and alert vs forecast distinction provide enough context for selection among siblings.

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