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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds substantial behavior beyond them: locked notes return locked=true without title/text, attachments appear as placeholders, hashtags/mentions render as text, and a prompt-injection safety warning about shared content. This is rich disclosure that annotations alone do not provide.

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 what is returned, then covers id sourcing, locked-note behavior, and the safety caveat in compact declarative sentences. Every clause is useful, though the density of edge-case details pushes it toward the long side.

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 single-parameter read tool with full annotations and an output schema, the description covers invocation source, return shape, edge cases (locked notes, attachment placeholders), and the security posture. Nothing an agent needs to call it correctly is missing.

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 0%, so the description must carry the payload, and it does by explaining that `id` is a result's id or identifier obtained from search_notes. That resolves the ambiguity of an otherwise undocumented string parameter, though it does not describe accepted formats or validation.

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 (read) and resource (one Apple Note), and enumerates the returned fields (title, folder, account, dates, body, attachments). It is clearly distinguishable from the sibling search_notes, which returns result identifiers rather than full content.

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?

Routes the agent to search_notes as the source of the `id`, giving clear context for how this tool is invoked. It does not explicitly state a when-not or name an alternative for other cases (e.g., reading an attachment), so it stops short of full routing guidance.

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