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

Annotations already declare readOnlyHint=false, destructiveHint=true and idempotentHint=true, so the safety profile is covered by structured data. The description adds the one thing annotations can't: a licensing gate (Standard plan or higher) that determines whether the call will succeed at all — exactly the kind of context worth surfacing. It stays silent on whether the overwritten status is recoverable or whether side effects like notifications fire, which keeps it short of a 5.

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, both short, with the allowed values and the plan gate front-loaded. Nothing redundant or padded.

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 2-parameter, fully documented, no-output-schema mutation, the description covers the essentials plus the plan gate. Only minor gaps remain (effect on the prior status, any downstream side effects), which are not needed for a correct call.

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% — both ticket_number (with a TKT-00042 example) and status (with a full enum) are documented. The description's enumeration of status values merely repeats the schema enum, adding no syntax or behavioral detail beyond it.

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?

States a specific verb (Set) and resource (a ticket's status) and enumerates the four legal values inline, so the operation's scope is unambiguous. It doesn't name a sibling or explicitly distinguish itself from get_ticket/list_tickets, but the write semantics are obvious.

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 plan prerequisite ('Needs the Standard plan or higher') gives real usage context, but nothing says when to reach for update_ticket versus draft_ticket_reply, reply_to_ticket, or set_access_tags on the same ticket.

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