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

Annotations already declare destructiveHint=true and idempotentHint=false, so safety is partly covered. The description adds non-obvious mutation semantics beyond the annotations: `user_tags` replaces the entire list, and archived uploads must be un-archived before content edits are permitted. That is meaningful behavioral disclosure, though permissions and concurrent-edit behavior are left unstated.

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 tight sentences with the field list front-loaded and the two critical constraints (tag replacement, archive precondition) clearly stated. No filler; every clause earns its place.

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?

An output schema exists, so return values need not be explained. The description covers the mutation surface and key state prerequisite for a 6-parameter update tool, missing only an explanation of what makes an upload 'verified' and any auth/permission context.

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 and does well: it maps title/description/tags/favourite/archived to concrete actions and importantly clarifies that `user_tags` is a full replacement rather than an append. Only the upload_id parameter and the significance of `archived: false` as a toggle are left implicit.

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?

Names a specific resource (upload) and enumerates the exact fields it can change — name, describe, tag, favourite, archive/restore. An agent instantly knows the operation, though no sibling (e.g. get_upload, delete_upload) is named to sharpen the boundary.

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?

Provides a real precondition (an archived upload must be restored before its words can change), which is useful operational guidance, but gives no when-to-use routing versus alternatives such as complete_upload or update_generation. Usage is implied rather than directed.

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