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

Annotations already declare readOnly, idempotent and non-destructive, so the safety bar is covered. The description adds genuinely new behavior: a fixed 30-day window, markdown output, and the important nuance that the device filter applies only to the behavioral portion, not the traffic portion.

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?

A single dense sentence, but it is front-loaded with the resource and metric list before the usage rationale. It is on the long side and slightly run-on, yet every clause (metric enumeration, optimize-loop purpose, device caveat, return format) carries information an agent needs.

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 carries the return-value burden and does so by enumerating the report contents and stating it returns markdown. For a two-parameter read tool this is close to complete; only failure behavior for a non-published pageId is left unstated.

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 already 100% with an enum on device, so the baseline is 3. The description goes beyond it by clarifying that the device filter affects only the behavioral half of the report, which the schema does not say and which materially changes how an agent will interpret the result.

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?

States a specific verb and resource ("Read real analytics for a published page") and enumerates exactly which metrics come back: traffic, sources, countries, browsers, devices, engagement, scroll depth, bounce rate, per-section click/exit/time. The word "real" implicitly separates it from the get_skill_analytics sibling, which is a guidance tool, but no sibling is named explicitly.

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?

Gives a clear use context — the optimize loop of finding the weakest section, changing it, republishing and comparing — and notes the device filter is optional. It scopes itself to published pages but never states what happens for drafts or which alternative to call instead, so the exclusions half of the guidance is missing.

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