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

Annotations already establish that this is a non-destructive write in a closed system, and the description adds meaningful context: the idempotency key requirement and the need for access to both source and destination Spaces. It stops short of describing conflict or overwrite behavior, so it is strong but not complete.

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 tight sentences with zero wasted text. The core action is front-loaded, followed by the key access prerequisite.

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 annotations and an output schema already present, the description covers the essential purpose, access prerequisite, and idempotency requirement. A note about what happens if the destination already contains the file would make it fully complete, but the remaining gap is minor.

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 only 20%, so the description must compensate, and it does conceptually clarify file version, source Space, destination Space, and idempotency. Still, it adds little detail about file_id/version formats or Space ID constraints beyond what the schema already shows.

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 states a specific verb ('Copy') and resource ('an exact file version') and clarifies the destination is another private Space. It is clearly distinct from space_file_create in intent, though it does not explicitly name or contrast with that sibling.

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 useful prerequisite — current access to both Spaces — and implies usage when copying an exact file version between spaces. However, it does not explicitly say when to use this instead of space_file_create or space_file_get, leaving selection partly inferred.

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