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

Annotations already declare readOnlyHint=false, destructiveHint=false and idempotentHint=false, but the description adds substantial non-obvious behavior beyond them: the default cluster is inherited from the session, archived clusters are refused, and binding is what grants the next work run the kubernetes/addon/stack tool families. It does not state whether a failed bind leaves prior state untouched, but the annotation bar is lower and the added context is rich.

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 the action and its clear variant before any justification. The long final sentence earns its place by explaining why binding matters, though the description is dense enough that a reader must parse several clauses to extract the caller rules.

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?

With zero required params, five optional params, 100% schema coverage and no output schema, the description covers identification, defaulting, clearing and refusal conditions. It omits what the tool returns or whether a successful bind is reported, a minor gap given no output schema exists.

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%, which sets a baseline of 3. The description exceeds that by stating the either/or identity relationships (ticket_number or ticket_id, cluster_name or cluster_id) and the session-cluster default for cluster, which the schema alone does not express.

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?

The description opens with a specific verb+resource+scope: 'Set which cluster an existing board ticket targets, or clear it with clear true.' It names the opposing sibling concept (ticket_get, ticket_update_status) implicitly by clarifying it operates on ticket targeting, and the clear/false dual behavior is unambiguous.

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?

Explicit when-to-use: 'Use this the moment an investigation narrows a ticket to one cluster.' It also names the failure mode that motivates the call (a board-level ticket dispatches into a session with NO cluster-scoped tools, so its agent cannot execute) and the refusal condition (archived clusters).

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