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

The annotations already establish that the tool is read-only and non-destructive. The description adds useful behavioral detail beyond that: the exact return shape and the important caveat that content is raw Gutenberg/HTML markup, not rendered output. The final Royally note partly restates the read-only annotation, but it also clarifies that the call runs without a confirmation step.

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?

The description is front-loaded with the core operation, then gives the return shape, content caveat, alternative tool, and read-only note in a logical order. The return-field list is long but each field is useful because no output schema exists. There is little wasted text.

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?

Because there is no output schema, the description usefully enumerates the returned fields and explains that content is raw Gutenberg/HTML rather than rendered output. It also names the CPT alternative and confirms the read-only behavior. For a simple single-resource read operation, this is complete enough to call 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 description coverage is 100%, so both `post_id` and `site_id` are already documented in the schema. The description only adds that the lookup is by ID and does not elaborate on `site_id` or any parameter behavior beyond the schema. A baseline 3 is appropriate because the schema carries the parameter semantics.

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?

The description states a specific verb and resource: gets a single WordPress post by ID. It also distinguishes the tool from a named sibling by directing CPT retrieval to `wp_get_cpt_item` instead. An agent can identify the operation 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?

The description gives one explicit routing rule: use `wp_get_cpt_item` for CPT items. However, it does not clarify when to use this versus close siblings such as `wp_get_post_full`, `wp_get_page`, or `wp_get_post_meta`. The main context is clear, but alternative selection is only partially addressed.

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