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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered; the description adds genuinely new context in the active-block-theme prerequisite and the full return field set. The closing line about the server marking it read-only largely restates the annotation, earning no extra credit but causing no harm.

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 purpose, then immediately the `type` semantics, ID format, and return shape — dense and well ordered. The final sentence about Royally's read-only marking is redundant with the annotations and is the one piece that does not earn its place.

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, and the description compensates by enumerating the returned fields and explaining `area` values per entity type. Combined with the prerequisite, ID format, and enum semantics, an agent has everything needed to call this 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?

Schema coverage is 100% and already documents all three parameters, so the baseline would be 3. The description nevertheless adds meaning beyond the schema by spelling out the `theme-slug//slug` ID format for both types and clarifying that `template_part` covers 'header, footer and other reusable areas', expanding on the terse enum 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 ('Gets a single block template or template part by ID with full content') and immediately disambiguates the two entity types via `type`. The word 'single' implicitly distinguishes it from list-style siblings such as wp_list_block_templates, so an agent can pick it correctly without opening the 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?

Gives a real prerequisite ('Requires an active block theme (Full Site Editing)') and explains which `type` value to choose for headers/footers versus templates. It stops short of naming an alternative tool for discovering IDs (e.g. list templates first) or stating exclusion conditions, so it lands at clear-context-but-no-routing rather than a 5.

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