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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so 'read-only, runs straight away' is a restatement of structured data rather than new disclosure. The only added value is the hard-coded site binding, and nothing is said about error behavior for a missing ID.

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?

A single front-loaded sentence with the verb and resource first; the site name and read-only note are tacked on but cost little. Minor redundancy with the annotations keeps it from a 5.

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?

For a two-parameter read with full schema coverage and rich annotations, nothing essential is missing. No output schema exists, so some hint about the returned post shape would have helped, but it is not required for correct invocation.

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 'id' documented as 'Post ID' and 'site_id' as a single-value enum, so the schema carries the parameter semantics. The description adds nothing beyond confirming lookup is by ID; baseline 3 applies.

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 single post by ID') and adds the qualifier 'any post type', which separates it from the page- and meta-specific getters in the sibling list. It stops short of naming a specific sibling to prefer, but the operation is unambiguous.

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?

'any post type' implies this is the general-purpose single-item fetch versus the typed/list variants, but there is no explicit when-to-use or when-not-to-use statement. The agent must infer that wp_get_posts lists and wp_get_post_meta/terms fetch sub-resources.

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