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

Goes beyond the annotations by disclosing the permission model (only the owner can change content or the setting, readers retain read access) and a real precondition — turning it on requires Pro. That explains why destructiveHint=true is set: enabling it removes editing ability from collaborators. It doesn't state what happens on a Pro-gated failure or whether disabling restores prior per-user permissions.

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?

Front-loads the core action in the first sentence and keeps the whole thing to four short sentences. The clause 'Only the owner can change it' largely repeats the preceding sentence about owner-only editing, leaving mild ambiguity about whether it refers to content or to the setting itself.

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 3-parameter mutation with no output schema, the description supplies the essentials: permission model, effect on readers, the Pro requirement, and the sibling that governs visibility. Minor gaps remain around failure behavior when not Pro and whether note and board differ in any way.

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% and the schema already explains id format, the note/board enum, and the boolean semantics precisely. The description adds no parameter-level detail beyond that, so the 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+resource+scope: toggling read-only on a user's note or whiteboard. It also separates the concern from set_access (which decides who can open it), so an agent can distinguish it from the access-control sibling without opening either 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?

Clearly frames the operation as a toggle ('on or off') and points to set_access for the separate question of who can open the item, which is the main routing ambiguity among siblings. It stops short of explicit when-not-to-use guidance (e.g., when the item is already in the desired state or when the caller isn't the owner).

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