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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description usefully adds the data scope (published posts only, rolling 7/14/30/90-day windows) and what dimensions are reported, which goes beyond the annotations without contradicting them.

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 primary action and metric scope in a single dense sentence, followed by a short orienting comparison. No padding, though the 'Insights page' clause is more marketing framing than operational guidance.

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 read-only, single-optional-parameter analytics tool with no output schema, the description supplies the returned metric set, which an agent would otherwise have to guess. Nothing critical to correct invocation is missing, aside from explicit guidance on when to prefer this over shop_overview.

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% with an enum on window_days, so the description only echoes the four allowed windows already in the schema and omits the stated default of 30. Baseline 3 is right when the schema carries the 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?

Names a specific resource (this Xyla shop's published posts) and enumerates the metrics returned — reach, views, engagement, followers per account, top posts. An agent can distinguish it from upcoming_posts or pending_approvals by the published/performance framing, though no sibling is explicitly called out.

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 'Same data as the Insights page in Xyla' line anchors the concept but does not say when to pick this over shop_overview or other reporting tools, nor any prerequisites or exclusions. Usage is implied by the metric list rather than stated.

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