renew_printer_lease

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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the mutation profile is covered. The description adds genuinely new behavioral information beyond that: the call can be REFUSED under two distinct conditions, including the race case where the lease lapsed and another holder took it. It omits what a successful renewal returns or whether a renewal can partially fail, though an output schema exists to cover returns.

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 sentences, zero filler, with the primary action stated first and the failure condition second. Every clause carries information an agent needs.

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?

The failure semantics are well covered and return values are handled by the output schema, but for a lease-management mutation the definition never explains the "minutes" argument or what happens if it is omitted — the one hole an agent must fill before calling. Adequate, not 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?

The single parameter "minutes" has 0% schema description coverage and is never mentioned in the description, so nothing clarifies whether it is an extension amount or a new total duration, or what the null default means (extend by a server-chosen increment?). With the only parameter completely unaddressed, the description fails to compensate for the coverage gap.

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?

"Extend your own lease" gives a specific verb (extend) and resource (your own lease), and the qualifier "your own" implicitly separates it from acquire_printer_lease, release_printer_lease, and break_printer_lease. It stops short of explicitly naming those siblings, so the differentiation is inferential rather than stated.

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?

"for a job that is taking longer than planned" supplies a clear triggering condition for when to call it, and the refusal clause tells the agent the precondition (you must currently hold the lease). It does not name what to do instead when refused — e.g. acquire_printer_lease or break_printer_lease — leaving the recovery path unstated.

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