ga4_get_realtime

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states what the tool returns (active users, top pages, traffic sources) but doesn't mention that it's a read-only operation, any authentication requirements, or potential rate limits. The only extra behavioral detail is the env var fallback for property_id, which is helpful but not sufficient for full transparency. The description leans heavily on the tool's obvious read-only nature without explicitly stating it.

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 extremely concise: two sentences plus an Args section. The main purpose is front-loaded in the first sentence, and the second sentence adds valuable detail about what the tool shows. The Args section is clean and directly relevant. No fluff or redundancy.

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?

The tool is simple, has only one parameter well documented, and an output schema exists (so return values need not be explained). The description covers the core functionality and purpose. It could potentially mention prerequisites or that it's read-only, but given the low complexity and existing output schema, the description is sufficiently complete for practical use.

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%, so the description must compensate. It fully explains the single parameter: property_id is a numeric GA4 property ID, and leaving it empty uses the GA4_PROPERTY_ID environment variable. This adds significant meaning beyond the schema's bare 'string type, default empty' and completely addresses parameter semantics.

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 specific action ('Get realtime active users and current events') and resource (the site's real-time data). It provides a clear sense of what the tool does without needing to infer. However, it does not explicitly distinguish this from sibling tools like ga4_get_top_pages or ga4_get_traffic_sources, which might overlap in scope, so it doesn't earn a 5.

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 gives clear context for when to use this tool: it shows what's happening 'RIGHT NOW', implying real-time monitoring. It doesn't explicitly mention alternatives or exclusions, but the 'right now' phrasing effectively communicates the intended use case. This meets the 'clear context, no exclusions' level.

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