mutations_cancel_mutation_plan

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

The description contradicts the annotations: it says 'Invalidate a pending local plan' (a mutation) while annotations declare readOnlyHint: true. This is a direct contradiction, and the description does not reconcile this by explaining that it only affects local state. Annotation contradiction is present.

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?

The description is a single, front-loaded sentence that immediately conveys the core function. Every word adds value, and there is no unnecessary 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?

Despite having an output schema, the description is too minimal to fully support an agent. It omits any explanation of parameters, side effects, or how it relates to the mutation plan lifecycle. The contradiction with annotations further reduces its reliability, making it incomplete for a tool that invalidates a plan.

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%, and the description does not explain what 'plan_id' and 'plan_hash' are or how they relate to the invalidation. With two required parameters and no added context, the description fails to compensate for the schema's lack of descriptions.

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 clearly states the verb 'Invalidate' and the specific resource 'a pending local plan', and adds the scope 'without changing Google Ads', which distinguishes it from apply/acknowledge siblings. It is concise and unambiguous about what the tool does.

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 description provides clear context: this tool is for invalidating a pending local plan, implying it should be used instead of applying or acknowledging it. However, it does not explicitly name alternatives or state when not to use it, so it falls short of a perfect score.

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