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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, yet the description adds real value: no provider write calls, no start approval, existing approvals for money/legal/historical campaigns left untouched, tenant projection scoping, and a freshness bound of at most 15 minutes on the stored page check. Only the return shape/pagination behaviour is left unaddressed.

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?

Three tight sentences with the resource and payload front-loaded, followed by scope/freshness and then the approval boundaries. The telegraphic style ('Keine Startfreigabe') is dense but every clause carries information; no 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 read-only, two-parameter tool with no output schema, the definition covers what data is returned, how fresh it is, whose projection it reflects, and which approvals it does not touch. That is enough for an agent to call it correctly; only pagination/result-size expectations are missing.

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 0%, so the description has to carry the parameters. It does map the two inputs semantically — 'Angebot' for offerKey and the explicitly 'optional Verkaufsfläche' for surfaceKey — but adds no format, length, or lookup-key guidance beyond that.

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 states a specific verb ('lesen') and resource ('Angebotsnachweise für Angebot und optional Verkaufsfläche') and enumerates the evidence payload (Preis, Storno, versionierte Policy, Angebotsabgleich, Zielseite). It is clearly a retrieval tool, but it never names the companion write path (submit_search_ads_evidence), so sibling differentiation is left implicit.

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 implied: read existing evidence for an offer, optionally scoped to a surface. The 'Keine Startfreigabe' sentence hints at a boundary, but it describes what the tool does not approve rather than when an agent should pick it over another tool. No explicit alternative or exclusion is stated.

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