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

Annotations already flag destructiveHint=true and openWorldHint=true, and the description still adds substantial behavioral context beyond them: edits propagate to every post using the pattern, an edit lock is checked, changes WordPress would strip are refused, a revision is saved, and an undo token is returned. It also discloses that in the Royally path the write is queued for human approval and nothing lands on the site until then, which is critical for an agent's planning.

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 first sentence front-loads the action and the propagation warning follows immediately, which is the right ordering. Density is high but nearly every clause carries information; the trailing site-name parenthetical and the 'Through Royally' sentence add some clutter without being wasteful.

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 destructive write with no output schema, the description covers side effects, validation/refusal behavior, revision creation, the undo token, and the approval gate. What it omits is failure-mode detail (what the response looks like when the edit lock blocks the change or when WordPress strips fields), which would complete the picture for a 4-parameter mutation.

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 75% and the schema already documents 'id' (with its source tool) and 'markup' with a format example, plus the site_id enum. The description only adds that title and markup are both optional-ish targets ('or both'), and leaves the undocumented 'title' parameter without further semantics; baseline 3 is appropriate.

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 ('Change a pattern's markup, title or both') that clearly separates it from wp_create_synced_pattern or wp_get_synced_pattern. It does not explicitly name a sibling to prefer in a given case, but the resource noun is unambiguous enough for an agent to route correctly.

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?

Usage is implied by the change-propagation warning ('changes every post that uses it') and the Royally approval gate, which tell the agent to be cautious. However, there is no explicit when-to-use versus alternatives (e.g., wp_update_block_attributes for a single block, or wp_update_post for an unsynced block), and no stated prerequisites besides the edit-lock mention.

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