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

Annotations already declare destructiveHint=true, idempotentHint=false, and openWorldHint=true, so the safety profile is covered structurally. The description adds one behavioral consequence (post_id preserves object metadata) but says nothing about permissions, what happens if menu_id is invalid, or whether re-calling creates duplicates despite idempotentHint=false.

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?

Two sentences, front-loaded with the action and followed by the single most important parameter decision. No filler or redundant restatement of the title.

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 7-parameter mutation tool with full schema descriptions, full annotation coverage, and no output schema, this is largely sufficient: the agent knows what it creates and how to pick the item type. It lacks any note on required connectivity/permissions or what the tool returns (e.g., new item ID), which an agent may need for follow-up calls.

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 the baseline is 3, but the description adds genuine meaning by explaining WHY post_id should be used ('keeps proper object metadata') rather than just restating the mutually-exclusive url/post_id rule already in the schema. It still says nothing about title, position, or parent_id beyond what the schema documents.

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 ('Creates a new custom-link or post/page-backed menu item in a navigation menu') and clarifies the two creation modes. It does not name a sibling or contrast with the many nearby create/menu tools, so it stops short of a 5.

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?

There is one actionable selection rule — 'Use post_id for WordPress pages/posts' — but no guidance on when to choose this tool over wp_update_menu_item or wp_create_menu, and no explicit exclusions or prerequisites. Usage is only implied from the verb.

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