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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description adds genuinely new behavioral context: the 'linked' vs 'copied' storage distinction and the fact that a linked file may require the user to re-grant access after a reload. That is a real caveat an agent would otherwise miss.

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, front-loaded with the core action and return shape, then the non-obvious storage caveat. No filler or restatement of the title.

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?

There is no output schema, so the description usefully names the returned fields and the one field with surprising semantics. It is nearly complete for a read-only list tool; only the lack of routing guidance against sibling media tools keeps it from full marks.

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 are documented in the schema, including 'Omit for all' for path, so the baseline of 3 applies. The description's detail about the `storage` field concerns return values, not parameter meaning, so it adds nothing to parameter semantics.

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 and resource ("Lists the user's media library") and enumerates the returned entity types (folders, files with id/name/kind/size/folder). It is separable from siblings like get_media or inspect_media, though it never explicitly contrasts itself with them.

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 only implied: the description shows what a listing yields, which suggests when to reach for it, but it never states when to prefer this over get_media, inspect_media, or organize_media, nor any prerequisite such as needing a connected session token.

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