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

Annotations already cover read-only/idempotent/no-destructive, and the description adds genuinely new behavior: permission-scoped visibility (drafts/pending/private/scheduled only when permitted), per-item `status` exposure, default page size of 10 sorted by most recent creation, and the WooCommerce dependency for `product`. It also flags the context-cost risk on large sites.

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 purpose and the do-not-use warning are front-loaded, followed by the return-shape facts and then parameter notes — a sensible order. It is dense but the trailing 'Through Royally: its server marks it read-only...' sentence is redundant with the annotations and slightly dilutes the close.

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: it describes the permission filter, the `status` field, the default count and sort order, and pagination support. For a 5-parameter, zero-required read tool, an agent has everything needed to call it 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?

At 60% schema coverage, the description earns credit: it explains what `search` matches (title and content), what `post_type` values mean ('all' includes posts, pages, and products when available), and the WooCommerce prerequisite for `product`. It says nothing about `page`/`per_page` beyond the schema's defaults and maximum, leaving a small gap.

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?

Opens with a specific verb and resource set ('Lists WordPress posts, pages and products with pagination support'), so an agent knows exactly what it returns. It doesn't name a competing sibling tool (e.g. wp_list_posts or wp_search_posts) to differentiate against, which keeps it short of 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?

Explicitly states the triggering condition ('Use ONLY when the user explicitly asks to list, browse, search, or reference existing site content by id') and an exclusion ('Do NOT call this as a default discovery step — on large sites the response is context-heavy'). That is the when/when-not pattern at full strength.

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