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

Annotations already declare the safe read-only, idempotent, closed-world profile, so the description's real contribution is scope disclosure: it states that UNFLATTERING results (predictions that missed) are included, which is exactly the kind of thing an agent should not have to discover empirically. It also discloses the shape of what comes back (totals, recent days, per competition, with match counts) — valuable since there is no output schema.

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?

A single dense sentence that front-loads the subject ('Die öffentliche Trefferbilanz von Prorakel') and then layers scope, evaluation timing, inclusivity of misses, and the three breakdowns. No filler, though the sentence is long enough that splitting the breakdown list would improve scanability.

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 zero required parameters, no output schema, and annotations covering the safety profile, the remaining burden is telling the agent what data it will get — and the description does so (overall values, last days, per competition, match counts). Only the time window implied by 'die letzten Tage' stays vague.

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 single optional parameter 'wettbewerb' is fully documented in the schema, including the note that the overall figure is always returned. The description's phrase 'je Wettbewerb, jeweils mit der Zahl der Spiele' reinforces what the competition dimension yields but adds no syntax or behavior 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?

The description names a specific artifact — the public hit/miss balance of Prorakel's predictions, evaluated after the final whistle, including wrong ones — and enumerates the breakdowns (overall, last days, per competition). That clearly separates it from sibling tools that list matches (spiele_am_tag, spieltag) or competitions (wettbewerbe), though no sibling is named explicitly.

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?

Usage is only implied: the mention of 'je Wettbewerb' hints that the optional competition filter narrows a per-league view, but there is no explicit statement of when to call this instead of a sibling tool or of any prerequisites. Nothing is misleading, but an agent must infer the choice itself.

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