ga_get_metadata

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

Annotations already declare readOnlyHint=true, so the description carries a lower burden. It adds a crucial behavioral disclosure: 'Response can be large (~500+ items). Use sparingly and cache results when possible.' This alerts the agent to response size and performance cost, beyond what the annotation provides.

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: the first states the purpose precisely, the second gives a necessary caution about response size. Every sentence earns its place; no redundancy or fluff.

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 zero-parameter metadata retrieval tool with no output schema, the description fully covers its scope and a key behavioral caveat. An agent can correctly decide to invoke it and understand the response implications. No gaps.

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 tool has zero parameters, so description need not explain parameter semantics. Per the rubric, 0 params yields a baseline of 4.

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?

Description clearly states the tool retrieves dimensions and metrics metadata for a GA4 property. The verb 'Get' and resource 'dimensions and metrics metadata' are specific, and it is distinct from sibling tools like ga_run_report which query data rather than metadata.

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 implies the tool is used to discover available metadata before running reports. The warning 'Use sparingly and cache results when possible' provides clear operational context on when to call. However, it does not explicitly mention alternatives or when-not-to-use.

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