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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description still adds real behavioural context beyond them: the URL is short-lived (implying it must be consumed promptly and re-fetched rather than cached), the scopes required for access, and a security note that returned text belongs in untrusted_fields and must not be executed as instructions. Only the absence of error/expiry specifics keeps it from a 5.

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 short sentences, no filler, and the core capability plus return value are front-loaded before the auth and safety details. The untrusted_fields clause is slightly compressed into one dense sentence, but nothing is redundant.

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 correctly covers the return value (a file plus a short-lived download URL) and adds mandatory auth context plus an injection-safety rule for third-party text. Missing only edge-case behaviour such as expired URLs, not-found files, or whether the URL must be regenerated via a separate call, which are minor for a single-parameter read.

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 the burden for the single required file_id param. It does not say where a file_id comes from, what format it takes, or whether it is globally unique — it merely implies the argument identifies the returned file. The parameter name is largely self-documenting, which prevents a lower score, but compensation for the coverage gap is incomplete.

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 names a specific verb and resource ("Get a file") and states the salient return value ("a short-lived download URL"), which distinguishes it from write-side siblings such as delete_file or import_file. It does not explicitly separate itself from near-neighbours like get_file_view_link or get_upload_link, so it stops short of full sibling differentiation.

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?

It gives a concrete precondition set (needs any of profile:read, content:read, inbox:read, bookings:read), which tells an agent whether it is authorized to call. However there is no explicit when-to-use versus when-not-to-use guidance, and no pointer telling the agent to prefer get_file_view_link or get_upload_link in the adjacent scenarios where those siblings would apply.

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