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

With no annotations, the description carries the full behavioral burden. It usefully discloses that results are limited to consecutive reports for the same water, that both sources and SHA-256 hashes are included where available, and that no cause is stated unless the utility provides one. It does not state read-only behavior, what happens when fewer than two reports exist, or the default scope when city is omitted.

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?

The description is a single compact sentence with no filler, and the core content is front-loaded. The nominal phrasing 'Werte, die ... stehen' is slightly less direct than an explicit verb would be, but nothing is wasted.

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 low-complexity tool with one optional parameter and no output schema, the description covers the returned content, provenance, and causal limitation well. The main remaining ambiguity is what happens when city is omitted, which leaves the default scope unclear.

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%, so the city parameter's format (slug, place name, or postal code) is already documented in the schema. The description adds no further meaning about the city parameter and does not clarify its optionality or default behavior.

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 specifies the resource and content precisely: before/after values from two consecutive reports for the same water, including source provenance and SHA-256 where files exist. It lacks an explicit verb and does not distinguish itself from siblings such as get_water_quality or compare_cities, so it falls short of a 5.

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 scenario is implied by 'zwei aufeinanderfolgenden Prüfberichten desselben Wassers', which tells the agent this is for comparing consecutive reports rather than general quality lookup. However, there is no explicit when-to-use guidance, no exclusions, and no named alternative among the sibling tools.

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