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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description still adds real behavior: the kit is read from one of the client's own sites, 'kit is null when the client has no kit yet, or the site has no client', and the data source is limited to Royally's records — the null case is the kind of detail an agent cannot infer from annotations.

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 what the kit is, then when to read it, then how to address it, then the null case — a sensible order with no filler sentences. The colour/font/variable/class enumeration is repeated in the usage sentence, a minor redundancy that costs it a point.

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?

No output schema exists, and the description compensates by describing the return shape (Site Settings colours and fonts, variables, classes) and the null case for 'kit'. For a two-optional-parameter read-only lookup with full annotation coverage, nothing an agent needs to call it correctly is missing.

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; the description earns an extra point by clarifying the selection logic beyond the schema — site_id resolves to 'the kit of that site's client' and either site_id or client_id may be passed (they are alternatives, not independent filters). That relationship is not obvious from two flat optional string properties.

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 (read/get) and resource (a client's brand kit) and enumerates its contents: Elementor Site Settings colours and fonts, Elementor 4 variables and Elementor 4 classes. It also scopes the retrieval ('read from one of their sites' and 'Reads Royally's records only'), which separates it from generic Elementor settings readers, though it never names the closest conceptual sibling (royal-mcp__elementor_get_kit_globals) explicitly.

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?

"Read it before you build or restyle an Elementor page on a client's site" gives a clear triggering condition, and "use these colours, fonts, variables and classes rather than inventing new ones" states the intended downstream behavior. No when-not condition or named alternative is given, so it stops short of full routing guidance.

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