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

With no annotations provided, the description carries the full burden of disclosing behavioral traits. It states the operation is a move (mutating), requires Manager role, and imposes constraints. However, it does not mention what happens to project data or billing history, nor does it discuss idempotency behavior of the idempotency_key parameter beyond what the schema provides.

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 three sentences with no wasted words. The first sentence states the primary purpose, the second adds a constraint, and the third adds a role requirement. It is front-loaded and easy to parse.

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 mutation tool with three parameters and no output schema, the description covers the essential context: what it does, constraints, and required role. It lacks details on expected return or failure modes, but given the simplicity, it is mostly complete.

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?

Since schema description coverage is 100%, the baseline is 3. The description adds no new parameter information beyond restating that project_id and new_customer_id are required, which the schema already specifies. The idempotency_key is only mentioned in the schema description.

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 the action ('Move'), the resource ('billing project'), and the context ('to a different customer within your organization'). It effectively distinguishes this tool from siblings like 'move_subtask' or 'move_task' by specifying 'billing project' and 'customer'.

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 for use ('Move a billing project to a different customer'), prerequisites ('Both project and destination customer must belong to your organization'), and a required role ('Requires Manager role or above'). It does not explicitly state when not to use, but the conditions are sufficient for proper selection among siblings.

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