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

Beyond the annotations (readOnlyHint=false, destructiveHint=false, openWorldHint=true) the description discloses that the password is generated server-side, that validation happens server-side, and — importantly — why WordPress folders are rejected: Plesk's protection covers the whole folder and would break the site or its login (e.g. admin-ajax.php). This causal explanation of a behavioral constraint is exactly the kind of context the annotations cannot carry.

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 core purpose and the strongest constraint (WordPress folders) are front-loaded in the first and last sentences, with the reading directive in between. It is a dense paragraph rather than a list, and the umlaut reminder partially duplicates the schema, but no sentence is wasted.

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 mutation tool with no output schema, the description covers effect, validation, and hard exclusions well. The notable gap is what the call returns — since the password is generated server-side, the agent is not told whether the response contains it, which matters for relaying credentials to the customer.

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 the baseline is 3; the description earns one step more by summarizing the cross-field rule (umlauts permitted in `title` but not in `directory` or `username`) and by directing the agent to the per-parameter rules before suggesting values. Most individual constraints still live in the schema, not the description.

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 names a concrete verb and resource — protecting a domain directory with HTTP Basic authentication — and spells out the effect (directory unreachable without login, hidden from search engines). It is unambiguous what the tool does, though it never names the sibling `remove_protected_directory` or any other alternative to contrast with.

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?

It gives clear operative context: the password is generated server-side, and WordPress system folders (wp-admin, wp-includes, wp-content) cannot be protected, which is a concrete exclusion an agent must know before calling. It also instructs the agent to read character rules before proposing values to a customer. It stops short of naming which sibling tool to use for the reverse operation or for other security measures.

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