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

With annotations offering no meaningful behavioral guidance, the description carries the burden and adds useful details: return format, inclusive date semantics, halfDay effect, overlap refusal, and free-tier limits. It does not contradict the annotations, and no annotation contradiction is present.

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?

Four short sentences, each with a distinct job: purpose/return, parameter semantics, validation behavior, and quota. Front-loaded with the core action and free of filler.

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 moderate-complexity tool with 6 parameters and no output schema, the description covers the action, return id, date/type/halfDay semantics, overlap behavior, and quota context. It could add explicit failure/error behavior, but what is present is sufficient for correct invocation.

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 coverage is 100%, so the baseline is 3. The description mostly restates what the schema already provides (type enum, inclusive dates, halfDay behavior), with the only notable addition being the LV-NNNN return id, which is not parameter-specific.

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 opens with a specific verb-resource pair ('Create a leave or PTO request') and states the return value (LV-NNNN id), making the tool's function unambiguous. It also contrasts naturally with siblings like leave_approve, leave_cancel, and leave_reject.

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 makes it clear this is for creating leave requests, but it does not explicitly state when to prefer this over sibling tools or mention exclusions such as checking balances first. Usage context is implied rather than explicit.

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