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

The annotations already declare readOnlyHint and openWorldHint, yet the description adds real value beyond them: free/open-data status, unchanged upstream measurements aggregated by Orb Studio, a 10-minute refresh cadence, and source attribution carried in the response. It does not disclose edge-case behavior (e.g. what happens when lat/lon fall outside Germany or when no stations report), which keeps it short of a 5.

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-loads the resource and units in the first clause, then packs coverage, defaults, disclaimers, and freshness into a short passage with no redundant restatement of the tool name or schema.

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 (station count, median/min/max, nearest stations, attribution), which is sufficient for an agent to decide and call. The one remaining gap is response shape/error semantics for out-of-range coordinates, a minor omission for a 2-optional-parameter read tool.

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 the schema already supplies the numeric ranges, so the baseline is 3; the description earns above that by explaining that lat/lon select a reference point and that Hamburg is the fallback when both are omitted — a default not expressed anywhere in the schema.

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 pair: 'Hourly mean ambient gamma dose rate in µSv/h from the BfS ODL measuring network', and enumerates the returned aggregates (station count, national median/min/max, nearest stations). This cleanly separates it from radiation-adjacent siblings such as get_space_weather, get_sensors, and get_marine_hydro_context.

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?

Gives a concrete default ('default Hamburg; optional lat and lon'), which tells the agent it can call with no arguments, and scopes the tool away from misuse by stating 'no thresholds, no alarm, no health assessment'. It stops short of naming an alternative tool for space-weather or health-risk questions, so the routing guidance is clear but not exhaustive.

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