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

Annotations already declare readOnly, idempotent, non-destructive, so "Rein lesend" largely repeats structured data. The description does add one genuine behavioral trait not in annotations — that this is cheaper than fetching raw rows — but it does not describe the shape of the aggregates returned. Modest added value against an already-covering annotation set.

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 with purpose and read-only nature, then routing to alternatives. The trailing "EN: report, chart, heatmap, map, dashboard..." keyword list is somewhat keyword-stuffed filler that doesn't add operational guidance, slightly reducing the density.

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 one-parameter, read-only tool with annotations and no output schema, the description covers purpose, usage, and what is returned (sums/averages). It doesn't enumerate which aggregate metrics are available, but that is a minor gap given the low complexity.

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?

Single parameter (report_id) with 100% schema description coverage, so the schema carries the semantics. The description adds no format, type, or constraint detail beyond what the schema already states, matching the baseline 3 for high-coverage schemas.

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: calculates report metrics (sums/averages) instead of individual rows. It explicitly contrasts with onto_report_json (raw data) and onto_report_map_data (map), so an agent can distinguish it from siblings without opening a schema.

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?

Explicit when-to-use ("when you need numbers instead of datasets"), with a named alternative for raw data (onto_report_json) and a named alternative for map display (onto_report_map_data). The selection conditions are clear and complete.

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