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

With readOnlyHint already declaring a safe read, the description adds real behavioral context: removed ad groups and groups of removed campaigns are filtered out, and campaign_status is returned to signal inherited campaign state (an ENABLED group under a PAUSED campaign is not running). That is non-obvious semantics an agent could not infer from the schema.

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?

Five short sentences with no filler, front-loaded with the purpose and filter, followed by the filtering caveat and parameter note. Tight and readable, though the campaign_status remark reads slightly like a data-model aside rather than invocation guidance.

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?

An output schema exists so return values need not be described, and the description covers purpose, filtering, hidden records, the campaign_status nuance, and the workspace parameter. The main residual gap is not naming campaign_id as the filter input and its format.

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 coverage is 0%, so the description must carry the load. It explains the workspace parameter well (customer workspace slug, optional when only one workspace exists), but campaign_id is only implied by 'nach Kampagne filtern' — its name and accepted format are never stated.

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?

States a specific verb and resource ('Ad Groups auflisten') plus the scoping capability ('optional nach Kampagne filtern'), which distinguishes it from write siblings like ads_create_ad_group. It does not explicitly differentiate from other list tools such as ads_list_campaigns or ads_list_ads, but the resource is unambiguous.

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: use it to enumerate ad groups, optionally narrowed by campaign. There is no explicit statement of when to prefer this over ads_list_campaigns or ads_list_ads, and no prerequisites or exclusions beyond the note that removed groups are hidden.

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