ga4_check_compatibility

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

There are no annotations, so the description carries the full burden of explaining behavior. It states only that the tool asks for compatibility, but does not describe the response format, how empty metric/dimension arrays are handled, whether the operation is read-only, or how compatibilityFilter affects results.

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 with no redundant wording. It could be slightly more direct if 'Ask' were replaced with 'Checks', but it is appropriately concise.

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 tool with six parameters, nested filters, no annotations, and no output schema, this description is incomplete. It does not explain what the compatibility response looks like, how filters interact with the check, or what the compatibilityFilter enum values mean. An agent would need to inspect the API documentation to use it reliably.

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 only 50%, so the description should compensate, but it provides no parameter-specific guidance. The only parameter detail comes from the schema; metrics, dimensions, and compatibilityFilter are left unexplained in the description.

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 identifies the tool as a compatibility check against the official GA4 Data API for proposed Core report dimensions and metrics. It is specific enough to convey the action and resource, though it does not name or distinguish sibling tools such as ga4_validate_query.

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 'with a proposed Core report selection' implies the tool is used when an agent has candidate dimensions/metrics and needs to verify compatibility before building a report. However, it gives no explicit guidance on when to choose this over alternatives, and no when-not-to-use cases.

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