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

Beyond the annotations, the description discloses the side effects (employee notified, leave applied to pay) and the important limitation that the action cannot be undone through this server. It also includes the endpoint, reinforcing that this is an external write operation.

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 front-loaded with 'WRITE' and the primary action, followed by the precheck, irreversibility warning, and endpoint. Every sentence adds useful operational context without waste.

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 destructive, non-idempotent write tool with no output schema, the description covers the action, side effects, reversibility, and required precheck. An agent has enough information to invoke it correctly and safely.

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%, so all three required parameters are already documented. The description includes the endpoint path with the same identifiers but does not add new semantic meaning beyond what the schema provides.

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 uses a specific verb and resource: approves a pending leave request. It also clarifies the operational effect—employee notification and application to pay—which distinguishes this write action from sibling read tools such as keypay_get_leave_request.

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 clear precondition: check the request first with keypay_get_leave_request. It does not explicitly mention the decline alternative or when not to approve, but the intended use context is clear.

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