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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds value on top: it scopes meta to 'non-protected' fields (disclosing a data limitation) and notes that Royally's server marks it read-only so it executes without a gating step. It does not contradict the annotations. It could say more about what happens with an invalid post_id, but for a read it is solid.

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?

Field list comes first, then the Elementor routing rule, then the execution note — front-loaded and each sentence carries information. The Royally framing sentence is slightly verbose relative to what it adds over readOnlyHint.

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, enumerating the returned fields is the right move, and it is done well. The Elementor route and read-only execution behavior round it out. Minor gap: no note on how missing/protected fields or invalid IDs surface.

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% with only post_id and a single-value site_id enum, so the schema carries the parameter burden. The description only adds the implicit hint that the same ID works for posts, pages, and CPTs. Baseline 3 applies since the schema does the heavy lifting.

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 ('Returns a single post/page/CPT') and enumerates exactly what comes back: title, content, status, author, dates, terms, non-protected meta, featured image. It also names the is_elementor flag and its meaning, so an agent can distinguish this from list-posts or get-post-blocks without opening a 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 explicit routing guidance: if is_elementor is true, edit with the Elementor tools rather than update-post. That is a real when-not rule. It stops short of stating when to prefer this over sibling readers like list-posts or get-page-structure, so it is clear but not exhaustive.

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