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

Annotations already mark idempotentHint=true and destructiveHint=false. The description adds value on top by specifying 'attach or replace' semantics, the private scope, the max length, and especially the special behavior that an empty string clears the note. No contradiction with annotations exists.

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 compact sentence delivers the core action, scope, length limit, and clearing behavior without any filler. The key information is front-loaded and every clause earns its place.

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, no-output-schema setter, the description sufficiently covers the operation, scope, length limit, and empty-string clearing. It does not describe return values or errors, but the tool's low complexity makes that omission minor.

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 0%, so the description carries some compensation burden. It adds meaning for 'note' by describing it as a private note and explains the empty-string clearing behavior, but it does not elaborate on creator_id beyond what the schema's UUID pattern already provides.

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 clearly states the action ('Attach or replace') and the resource ('your private note on a creator'), with a concrete length constraint. This makes the tool's purpose immediately understandable and distinguishes it from creator save/unsave or list operations in the sibling set.

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?

The description conveys clear context: use this tool when you need to create, update, or clear a private note on a creator. It does not explicitly name alternatives or when-not-to-use conditions, but no sibling tool has an overlapping purpose, so the usage context is sufficient.

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