Download MeteoEurope1km grid archives

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

Annotations declare non-read-only, idempotent, non-destructive and open-world, and the description adds genuinely new behavior: 1-3.5 GB per year of daily data, MD5 verification, and resumption of interrupted downloads. It doesn't say whether existing files are overwritten, where the files end up beyond the schema's dest_dir default, or what the tool returns, so it earns a 4 rather than 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?

Two short paragraphs, front-loaded with the operation and its size/cost implication, followed by the safety-relevant resume behavior and the caller-side instruction. No sentence 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?

For a six-parameter download tool with no output schema, the description covers cost, integrity checking, resumability and the required pre-step. The main remaining gap is what the call returns (file paths? manifest?), which matters for chaining a subsequent read, but the operational essentials are present.

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 83% and the schema already explains product, years, period, dest_dir and variable in detail; the description adds only the 'optionally unzip' framing, which is largely implied by the unzip boolean. Baseline 3 is the correct call when the schema carries the parameter burden.

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 (Download) and a named resource (MeteoEurope1km archives) with key attributes in the same breath: per-year archive size, MD5 verification, optional unzip. An agent can tell this apart from list_gridded_files, which it explicitly frames as the sizing/listing sibling.

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 workflow rule — call list_gridded_files and tell the user the total size before large downloads — which routes the agent to the right sibling at the right moment. It lacks explicit when-not guidance (e.g. point data should use get_weather instead of downloading archives), so it stops short of a 5.

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