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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, so safety is covered; the description adds the non-obvious capability requirement 'Requires manage_options', which the annotations do not express. It also restates read-only behavior ('runs straight away'), which is mildly redundant but confirms no confirmation gate. It stops short of noting any cost/latency of the aggregate call.

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?

Purpose is front-loaded in the first clause and the return-field list earns its length by enabling tool selection. The trailing '(site: ...)' and 'Through Royally: read-only, runs straight away' are boilerplate that repeats the enum and the annotations, slightly diluting an otherwise tight definition.

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?

There is no output schema, so the description carries the burden of describing returns — and it does so exhaustively, down to WP_DEBUG_LOG state and disk free space. Combined with the auth prerequisite and the sibling-routing guidance, an agent has everything needed to call it correctly in one shot.

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 description coverage is 100% and the single site_id parameter already carries its enum value with a URL. The description only adds the parenthetical '(site: demo.royalplugins.com)' as ambient context, not new parameter semantics. Baseline 3 is appropriate when the schema does all the work.

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+resource ('One-shot site diagnostic') and then enumerates the exact fields returned (WP version, PHP version, MySQL version, plugin count, theme details, memory limit, upload size, timezone, WP_DEBUG_LOG, disk free, install age, URLs). It explicitly distinguishes itself from nearby siblings wp_get_site_info, wp_get_plugins, and wp_get_active_theme by presenting itself as their composite.

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 an explicit trigger ('at the start of a debugging or environment-inspection conversation') and an explicit substitution rule ('instead of piecing it together from wp_get_site_info + wp_get_plugins + wp_get_active_theme'). The agent knows both when to call it and which siblings to skip.

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