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

The description goes well beyond the annotations (readOnlyHint=true, idempotentHint=true, destructiveHint=false) by detailing the exact permission requirements and the error message behavior, the window of whole UTC days, the separation of page paths and in-app sections, and the explicit list of data that is never returned (per-visitor rows, emails, IP hashes, etc.). This provides rich behavioral context that annotations alone do not convey.

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 dense paragraph that packs a lot of information. It is front-loaded with the key purpose and differentiators, but the length is substantial. While every sentence adds value, the density could be slightly improved with better structure (e.g., separating permission requirements from data details). Still, it is efficient and avoids 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?

Given the tool's complexity (multiple metrics, permission requirements, exclusions), the description is remarkably complete. It covers what is returned, what is not returned, the window semantics, the permission model, and the relationship to sibling tools. The output schema exists, so return values are documented, and the description adds the necessary context for correct invocation.

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 schema already documents the 'days' parameter with a description, min/max, and default. The description adds context about the window being whole UTC days ending today, which aligns with the schema. Since schema coverage is 100% and the description reinforces the semantics without adding new parameter-specific details, a score of 4 is appropriate (baseline 3 plus the added context about UTC days).

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 tool returns visitor traffic for the META COUNCIL PLATFORM's own website, explicitly distinguishing it from workspace metrics and business rollup metrics. It names the specific metrics returned (views, unique visitors, split, paths, sections, referrers, per-day series) and the window covered, making the purpose unambiguous.

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 explicitly states when to use this tool (for platform website traffic) and when not to (not for caller's workspace, not for business rollup), naming the alternative tools get_workspace_metrics and get_meta_council_platform_metrics. It also specifies the required permissions (platform:admin scope AND ADMIN_EMAILS operator account) and the error behavior for unauthorized callers.

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