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

Annotations only mark this destructive/non-idempotent; the description goes further, disclosing the exact side effects (ticket marked closed plus a 'closed by the customer' thread note) and an operational limitation (the support team's own board is not moved). This is behavior an agent could not infer from the structured fields.

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?

Front-loaded with purpose, then usage rules, then identification, then the caveat. Every sentence carries distinct information, though the final 'known gap' sentence is dense enough that it could be split for readability.

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 mutation tool with no output schema and no annotation detail, it covers side effects, authorization scope, and the limitation clearly. It does not say whether a close can be undone or what happens on a repeat call, which matters given idempotentHint=false.

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% and both parameters are already documented, so the schema does the heavy lifting. The sentence 'Identify the ticket by ticket_number or ticket_id' adds only the either/or relationship, which the schema descriptions already imply. Baseline 3.

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?

Specific verb+resource ('Close a support ticket from the customer's side') with the mechanical consequence stated (marked closed, note added) and an equivalent CLI reference. It is clearly separable from comment_support_ticket, the sibling it explicitly contrasts itself with.

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?

Gives an explicit when ('only when the user says the matter is resolved or no longer needed'), an explicit when-not ('do not close on support's behalf'), and routes the alternative case to comment_support_ticket when support is still expected to act.

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