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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile is covered. The description contributes beyond that by disclosing two behavioral traits the schema cannot: the link is short-lived (callers must not cache it) and the response carries a ready-to-run curl command. It stops short of saying how long the link lasts or whether the command is a string field.

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 with the key qualifier ('short-lived') and the deliverable ('curl command') front-loaded. Nothing is wasted and nothing is buried.

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, non-destructive read with full schema coverage and no output schema, the description covers purpose, the ephemeral nature of the result, and the shape of what comes back. It could be stronger by noting expiry duration or that only files visible via list_files can be fetched, but an agent has enough to call it correctly.

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 both parameters ('path' with its example and cross-reference to list_files, 'project_id' with its link to list_projects) are fully documented in the schema. The description adds no parameter-level meaning, 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?

The description clearly identifies the resource (a library file) and the outcome (a short-lived link plus curl command for downloading it into your own environment). It is distinct from sibling read tools like list_files or get_file_content, though that differentiation is only implied by 'download ... into your own environment' rather than stated against a named alternative.

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?

Usage is implied rather than stated: an agent can infer this is the tool for pulling file bytes locally, as opposed to listing (list_files) or inspecting metadata. There is no explicit when-to-use/when-not, no mention of prerequisites (does the caller need the file to exist or permissions on the project?), and no guidance on link expiry handling.

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