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

Annotations already declare readOnlyHint=true, so safety is covered; the description adds real value by disclosing the three failure modes (not-wordpress, not-live, not-running), which lets an agent anticipate preconditions. It does not cover auth requirements or cost/latency, so it stops short of a 5.

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 front-loaded sentence listing outputs, followed by a compact refusal clause — no filler. Slightly dense enumeration, but every clause carries information an agent would otherwise have to discover by calling.

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 an output schema present, the return-value enumeration is mildly redundant but the refusal modes fill a genuine gap. What remains missing is routing guidance relative to the wp_* mutation siblings, which is a minor gap for a simple single-param read tool.

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?

One parameter (serviceId) with 100% schema description coverage, so the schema already explains it; the description offers no additional guidance such as how to obtain a serviceId or what happens with a non-WordPress service id. Baseline 3 applies.

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/resource ('a live WordPress site as WP-CLI reads it') and enumerates exactly what is reported: core version, plugin/theme statuses and updates, active theme, site and admin addresses. This distinguishes it cleanly from the mutating siblings wp_core_update, wp_plugin and wp_theme.

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 read-only status framing implies it is the inspection step before wp_core_update / wp_plugin / wp_theme, but the description never says when to use it instead of those tools. No explicit preconditions or exclusions beyond the refusal list.

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