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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds material behavior the annotations cannot: results are metadata only and filenames are encrypted and unavailable, which prevents an agent from expecting usable file identifiers.

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 compact sentences with zero filler; the most decision-relevant constraint (what data is and isn't returned) is front-loaded before the parenthetical detail.

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 usefully enumerates the return shape (sizes, status, counters, expiry) and the critical absence of filenames. Minor gap: no mention of pagination behavior despite the limit parameter capping at 100.

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%, with both the limit cap ('At most 100.') and the full status enumeration documented in the schema itself. The description adds no filtering or pagination semantics on top, so 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?

Specific verb+resource ('List this account's file shares') with an explicit scope limit and a summary of returned fields. It does not explicitly contrast with the sibling get_share, but the list-vs-get distinction is inferable from the name and the 'metadata only' qualifier.

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 context is implied rather than stated: 'metadata only' signals that this is an overview call, not a way to retrieve file contents or a single share's detail. No explicit 'use get_share when...' routing or prerequisite guidance is given.

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