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

Goes beyond the annotations by disclosing output-affecting behavior: sensitive keys (API keys, secrets, tokens, passwords) are redacted and protected options are omitted, so the agent knows results are intentionally incomplete rather than missing. The read-only/immediate-run remark only restates readOnlyHint and adds nothing, which caps the score below 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?

Front-loaded with the purpose and matching rule, then the important exclusions (core prefixes, redaction) in descending priority. The trailing site identifier and 'Through Royally: read-only, runs straight away' boilerplate duplicates structured data and could be dropped.

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 supplies the key behavioral facts an agent needs (matching rule, redaction, exclusions) so results aren't misread. It stops short of saying how results are shaped (option name to value mapping) or whether the list is paginated, which would fully close the gap.

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%, so baseline is 3, and the description earns a bump by explaining that plugin_slug accepts either the full slug or a short option prefix and clarifying exactly which option names that matches — meaning the schema text does not convey. site_id is only explained by the enum/schema, not by the description.

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 ('Get all options stored by a plugin') plus the exact lookup semantics (slug or option prefix, matching <slug> or <slug>_*). It explicitly carves itself away from the sibling wp_get_option by refusing core option prefixes, so an agent can route without opening either schema.

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?

Names the alternative ('use wp_get_option') and the condition that selects it (WordPress core option prefixes are refused). The slug-vs-prefix example ('royal-affiliate-pro' or 'rafp' for rafp_* options) tells the agent how to phrase the call in ambiguous cases.

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