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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered. The description adds genuinely new behavior: images (max 3) are returned as image content after the text, and list results expose only short-lived signed URLs. It stops short of describing pagination, size limits, or failure modes.

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?

Three sentences, each doing distinct work: what it returns, how images are delivered, and why the sibling tools' URLs are insufficient. Front-loaded with the primary purpose and no filler.

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?

With no output schema, the description carries the return-value burden and does explain text, metadata, and image content ordering. Metadata is mentioned but never itemized, which is a minor gap for a tool whose whole job is retrieval.

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 100% and both parameters are documented, including the default for include_images, so the baseline is 3. The description adds value beyond the schema by capping images at 3 and specifying they arrive after the text, but note_id format/source detail is left to the schema.

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 precise verb and resource ('Fetch a single note's full text and metadata by its id'), and the singular scoping implicitly separates it from the plural list/search siblings. The image-handling sentence further pins down what the tool uniquely does.

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?

Gives an explicit routing rule: results from the other tools surface images as short-lived signed URLs, so 'call this tool to view them.' That is a real when-to-use condition tied to a sibling behavior, though it doesn't state exclusions or prerequisites (e.g., what happens for a nonexistent id).

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