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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read nature is covered. The description adds that returned experiments include status and runtime, which gives useful return context beyond the annotations. It says nothing about pagination, empty results, or permissions, so it only modestly adds value.

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?

Two short sentences with no filler and the purpose front-loaded. However, it is sparse to the point that no real usage or behavioral context is provided — the brevity is as much under-specification as efficiency.

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?

Output schema exists, so return values needn't be fully explained, and the single parameter is addressed. Still missing scope (all experiments in the account vs. per campaign) and any sibling differentiation for an agent navigating a very large toolset.

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 must carry the one parameter — and it does: 'workspace: Slug des Kunden-Workspace (optional bei nur einem Workspace).' That explains what the param is and its optionality condition, compensating for the schema gap. It doesn't give format examples or how to discover the slug, keeping it at a solid 3.

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?

Written in German, it uses a clear verb+resource: it lists campaign experiments (A/B tests) with status and runtime. There is no sibling tool for experiments, so no disambiguation is needed among the 180+ siblings. Lacks scope detail (which campaign, whole account), preventing 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?

No indication of when to use this versus ads_list_campaigns or the other list tools, no prerequisites, no exclusions. The agent must infer from the name alone whether listing experiments is the right action.

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