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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds crucial behavioral context: URL expiry (15 minutes), no-login access, and treating it as a credential. This goes beyond annotations with no contradiction.

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?

Two sentences with zero filler. The core purpose is front-loaded, and the expiry/security note is concise. Every sentence 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?

Complete for a low-complexity tool with fully documented parameters and helpful behavioral notes. The description mentions the response field (download_url_expires_at) even though there is no output schema, covering the return behavior adequately.

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% with clear descriptions for both parameters. The description adds value by specifying that file_id comes from notes-get response, which is not in the schema, and reiterates the required relationship. This is a slight enhancement over the baseline.

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: 'Get a time-limited download URL for a file attached to a note.' It clearly differentiates from sibling file operations (attach, remove, upload) and includes the intended use case (share with user).

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?

Provides clear context: when to use (to download in browser) and practical guidance (request fresh URL instead of reusing old). Lacks explicit exclusions or alternatives, but the purpose is narrow enough that no alternative is needed.

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