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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description's real contribution is disclosing that results are permission-scoped across four visibility tiers (owner, shared with you, your team, your channels), which is behavior an agent cannot get from the annotations. It omits result volume, ordering, and whether a partial or paginated set is returned.

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?

One short sentence with no filler, and the visibility scoping is front-loaded. It is a grammatically incomplete fragment ("your owner's" with no noun), which is slightly cryptic but does not pad the definition.

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 simple read-only enumeration tool with a fully documented single parameter and complete annotations, the description covers the key non-obvious fact: the result set is permission-scoped. It stops short of the practical details an agent needs to call it well, namely whether results are limited, sorted, or paginated.

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 the single optional parameter "query" is documented in the schema as "Part of a file name". The description adds no guidance on the parameter, such as whether it is a substring match or how it interacts with the visibility scoping. Baseline 3 applies when the schema does the work.

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 text describes the result set ("Files you may see: your owner's, and those shared with you, your owner, your team or one of your channels") rather than stating an action. Combined with the name files_list and title "List files", an agent can infer the purpose, but the description itself carries no verb and never says it lists or searches files. It does usefully scope which files are visible, which distinguishes it from files_get.

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?

There is no when-to-use guidance: nothing tells the agent to prefer this over files_get for retrieving a specific file, or over files_versions when version history is needed. The sibling list is dense with related file tools, and none are named or excluded. The reader must infer that this is the enumeration entry point from the name alone.

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