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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds real behavioral context beyond the annotations: only keywords in ENABLED campaigns, restricted to the 100 highest-impression keywords, and the reporting window excludes today. This materially changes what results an agent should expect.

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 the metric components, followed by scope, return fields, and parameter notes — every block earns its place. The line-wrapped pseudo-structure makes it slightly harder to scan than a clean sentence flow, but there is 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 two-parameter read-only reporting tool it covers everything an agent needs: population filters, time window semantics, per-parameter meaning, and result shape (quality_score 1-10, three enum components, impressions, clicks) even though an output schema already exists. Nothing essential to calling it correctly is 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 carries the full burden and largely does: 'days' is defined as a lookback period with default 30 and today excluded, and 'workspace' is described as a customer slug that can be omitted when only one workspace exists. Minor gaps remain (no upper bound on days, no format example for the slug).

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?

Names a specific resource (Quality-Score-Komponenten je Keyword) plus the three metric components and the analytical intent (Landingpage-Arbeit). An agent can tell this is a keyword-level quality diagnostics tool rather than a mutation or listing tool. It does not, however, differentiate itself from the closely related ads_keyword_performance sibling.

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 phrase 'für gezielte Landingpage-Arbeit' implies the intended use case, and the scope line (only ENABLED campaigns, top 100 by impressions) hints at when the tool fits. But there is no explicit when-to-use/when-not framing or a named alternative such as ads_keyword_performance or ads_list_keywords, which an agent must infer.

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