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

Annotations already declare readOnlyHint=false, destructiveHint=true and openWorldHint=true, so the safety profile is carried structurally; the description adds the useful clarification that status is not mutated. It does not address visibility of the reply to the customer, whether replies can be edited or removed, or permission requirements, which matters given a destructiveHint of true.

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?

A single sentence with no waste, front-loading the action and immediately qualifying it with scope and side-effect behavior.

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 three-parameter, 100%-documented write tool with annotations covering the safety profile and no output schema, the description supplies the one piece of context the schema cannot: that the ticket status is unaffected.

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 parameters (ticketId, message, intentId) are already documented in the schema. The description adds nothing parameter-specific and only hints at scoping; baseline 3 applies when the schema does the work.

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 and resource ("Add a reply on a support ticket") plus a scope constraint ("in your scope") and a side-effect guarantee ("without changing its status"). It does not differentiate from the sibling UpdateTicket, which also touches tickets, so it stops short of a 5.

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 "without changing its status" clause implies when to prefer this over a status-changing tool like UpdateTicket, but that routing is left to inference. There is no explicit statement of when to use this versus UpdateTicket or any prerequisite/eligibility condition.

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