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

Annotations only declare readOnlyHint=false, destructiveHint=false, openWorldHint=false. The description adds genuinely valuable behavior beyond them: it returns the viewer link and that current viewers are disconnected when visibility changes. The disconnect side effect is not captured by destructiveHint=false, though it is a session-level disruption rather than data destruction, so this is added context rather than a contradiction.

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 compact sentences: the operation first, then the observable return and side effect. No filler, and the most decision-relevant information is front-loaded.

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 no output schema, the description helpfully names the return value (viewer link) and the disconnect consequence, which is the main completeness win. However, for a mutation tool it omits auth/permission expectations and leaves the session and agent_token parameters unexplained, so an agent still guesses at invocation details.

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% and there are no enums, so the description must carry the parameter burden. It partially compensates by listing the accepted visibility values (private, link, public), but says nothing about the 'session' and 'agent_token' parameters, leaving two of three undocumented anywhere.

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 ('Change') and resource ('visibility') and enumerates the allowed values (private, link, public), so an agent knows exactly what the tool does. No sibling is named, but none of the siblings (session, capture, bench, queue tools) overlap meaningfully, so differentiation is less critical.

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 description never says when to use this tool, what preconditions exist (e.g. an open session, ownership, auth), or how it relates to any alternative. The only implied guidance is the enumeration of visibility values, which is not usage guidance.

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