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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the description is not responsible for those basics. It adds valuable behavioral information: 'Importers of the source are left unchanged' clarifies a non-obvious side effect, and 'same type only' sets an important constraint. This goes beyond the annotations without contradicting them.

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?

The description is two sentences with no wasted words. It front-loads the core purpose with an example, then covers constraints and batching efficiently. Every sentence 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?

For an operation that copies multiple items, the description covers the main behavioral details: naming rules, type constraints, side effects on importers, and batch invocation. The schema handles parameter structure. There is no output schema, so return values need not be explained. Minor gaps like error handling or directory recursion are not critical for an agent to call this tool correctly.

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 must compensate. It explains the semantics of 'from' and 'to' through the example and the naming rules, and clarifies that 'copies' is an array applied in one call. However, it omits any context for 'expected_version' and 'projectId', which are also required. The description adds some meaning but does not fully cover all parameters.

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 clearly states it copies items to new names, with a concrete example. It distinguishes itself from siblings like rename_file by explicitly noting that importers of the source are left unchanged, which is a key differentiating behavior. It also adds constraints ('same type only', 'without extensions') that define scope precisely.

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?

The description provides clear context: 'Importers of the source are left unchanged' implies that rename_file would be the alternative if importers should be updated, and 'Pass several copies to apply them in one call' gives batching guidance. However, it does not explicitly name an alternative tool or state when not to use it, leaving a small gap.

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