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

Annotations already declare destructiveHint=true, idempotentHint=true, and openWorldHint=false, covering the safety and repeat-call profile. The description adds two pieces of context annotations do not carry: the conversation must be customer-owned and the action requires explicit confirmation. It still omits consequences of closing (message history retained? customer able to reply?) and error cases such as already-closed conversations.

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 front-loaded sentence with zero filler. Every element (scope, ownership, confirmation requirement) earns its place.

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?

A destructive mutation with no output schema and 0% parameter documentation needs more than one sentence. Annotations cover safety and idempotency, and confirmation is enforced by the schema, but the description says nothing about post-close state, irreversibility effects on the customer, or failure modes.

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 0%, so the description must compensate. It loosely maps to both parameters: 'one ... conversation' implies a single conversationId, and 'after explicit confirmation' corresponds to the required confirmed=true const. It adds no syntax, format, or ownership-validation detail beyond that hint, leaving the burden on the schema's uuid pattern and const.

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+resource ('close ... conversation') plus scope qualifiers ('one', 'customer-owned'), so the operation is unmistakable. It does not name or differentiate from siblings like support_conversation_create or support_conversations_list, which a 5 would require.

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?

'after explicit confirmation' gives a gating condition for invoking the tool, which is real usage guidance. However, there is no mention of alternatives (reopen, escalate, reply via support_message_send) or when NOT to close a conversation.

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