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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so the safety bar is met structurally; the description adds genuinely new behavioral facts instead: data provenance (IBB, Gutachterausschuss), vintage (2025 rent, H1 2026 sales), and the sort order ('teuerste zuerst, mit Bezirk'). It does not disclose payload size, response shape, or price units, which keeps it from 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?

A single dense sentence with no filler, front-loaded by the 'Berlin gesamt' scope marker. It is somewhat over-packed with comma-separated items, and abbreviations like 'Ø-Angebotspreise' and 'Kauffälle' ask the agent to decode domain shorthand, but nothing is redundant.

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 must carry the return-value burden, and it does enumerate the datasets returned, their time windows, and their ordering. It falls short only on structural details an agent would want before calling (JSON shape, units, whether ranking and rents are separate blocks in one response).

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?

The tool takes zero parameters, so the baseline is 4; there is no parameter semantics to convey and the description correctly spends no space on inputs. It could only reach 5 by explicitly stating that the call is parameterless and returns a fixed scope, which it does not.

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 concrete resource and enumerates exactly what the payload contains: city-wide average asking prices, a ranking of all 97 Ortsteile plus two Umland towns, IBB asking rent 2025, and Gutachterausschuss notarized sales. 'Berlin gesamt' implicitly separates it from area-scoped siblings like get_area_prices, but no sibling is ever 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?

There is no statement of when to call this instead of get_area_prices, get_bodenrichtwerte or the other siblings, and no exclusions or prerequisites. Only a weak scoping hint ('Berlin gesamt', i.e. whole-city rather than single-area) implies the intended use, and the agent must infer that comparison itself.

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