get_custom_dimensions_and_metrics

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

No behavioral traits disclosed beyond being a read operation. With no annotations, the description fails to mention any side effects, permissions, rate limits, or performance characteristics.

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 sentences with no wasted words. The main purpose is front-loaded, and the parameter clarification follows efficiently.

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 simple single-parameter tool, the description explains the parameter format but omits return structure details. Given no output schema, more context on expected response would improve completeness.

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?

The description adds format guidance for property_id (number or 'properties/' prefix), which the schema lacks. This compensates for 0% schema coverage, though only one parameter is detailed.

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 it 'Returns the property's custom dimensions and metrics.' This is a specific verb+resource combination that distinguishes it from sibling tools like get_account_summaries or run_report.

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 guidance on when to use this tool vs alternatives. The description only states what it does without providing context about typical use cases or when to prefer it over siblings.

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