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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered; the description still adds meaningful behavior: 'include_extras reads saved extras only and never starts a sync' (a key no-side-effect guarantee), a plan-gating requirement for insights, and 'most recent first' ordering with limit/offset. It does not discuss error behavior for missing account_id or rate limits, keeping it below the top mark.

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?

Front-loaded with the platform list, then organized view-by-view so the reader can scan to the relevant section. It is dense and a bit long, but each clause carries substantive detail (metrics, filters, plan gating, no-sync note) rather than repetition.

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?

With no output schema, the description still conveys what each view returns (metric names per platform, feedback tier/diagnosis/next action/baseline), pagination defaults, and presentation formats. A fuller account of the response envelope (e.g. summary vs snapshot shape) would be needed for a 5, but this is sufficient to call the tool correctly.

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 coverage is 100%, so the baseline is 3, but the description adds cross-view applicability the schema only implies: which parameters apply to accounts, posts, and insights, that presentation is valid only for accounts/posts, and that include_extras is accounts-only. This conditional parameter routing is genuine value beyond the schema.

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 names the resource (analytics for connected accounts), enumerates the platforms, and enumerates the three views with the specific metrics each returns. An agent can distinguish it from list_posts or list_comments because it explicitly frames output as snapshots, summaries, and per-post metric rollups tied to a view selector.

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?

It gives per-view routing guidance, including the non-obvious rule that Google Business per-post rows do not exist and its totals live on view=accounts, plus the Pro-plan-or-higher prerequisite for view=insights. It stops short of naming sibling tools (e.g. list_posts, list_comments) as alternatives for raw post/comment data, so exclusions are implicit rather than explicit.

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