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

Annotations cover the safety profile (readOnlyHint, openWorldHint, destructiveHint), and the description adds real context beyond them: conditional behavior when the water module is active, the 15 km gauge radius, the absence of official warnings, and a license/source trailer on the response. It stops short of failure modes such as ambiguous place names or what happens when the module is inactive.

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?

Front-loaded: the full content scope is in the first sentence, followed by examples and then the license note. Three example questions is slightly more than needed, but each sentence carries information and none 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?

With no output schema, the description carries the burden of describing returns and does so: weather, nowcast, 24-hour forecast, gauges, and the source/license footer. For a one-parameter, read-only, annotated tool, nothing an agent needs to invoke it correctly 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?

Schema description coverage is 100% and there is a single parameter, so the schema already documents the accepted 'ort' formats (name, GKZ, coordinate). The description adds nothing about the parameter, which is the expected baseline when the schema does the heavy lifting.

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 and resource (an all-in-one overview for an Austrian municipality) and enumerates exactly what is bundled: current weather, 3-hour nowcast, 24-hour forecast, and nearby gauges within 15 km. That enumeration is what separates it from the single-purpose siblings like niederschlag_jetzt, wetter_prognose and pegel_in_der_naehe.

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 three example questions ('Wie ist die Lage in Steyr?', etc.) make the intended usage concrete, and 'Keine amtliche Warnung' tells the agent this is not the tool for official warnings. However, no sibling is named as an alternative, so the routing to hochwasserlage or wetter_prognose is left to inference.

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