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

The description asserts 'Nothing is read or changed', directly contradicting annotations that declare readOnlyHint=false, destructiveHint=true, and openWorldHint=true. An agent reading both signals gets flatly incompatible safety profiles for the same tool. The honesty about the tool being unsupported is useful, but the explicit side-effect contradiction forces the lowest score.

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?

Three short sentences, each carrying a distinct load: the reason, the support status, and the side-effect guarantee. The critical information (nothing to clear, not supported) is front-loaded with no filler.

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 stub tool the description covers the essentials — no effect, not supported — and there is no output schema to explain. However, it leaves unexplained why a no-op exposes four parameters including a monetary acknowledgement field, and gives no guidance on whether invoking it is harmless or returns an error, which an agent needs in order to decide between calling and refusing.

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?

All four parameters (orgId, confirm, idempotencyKey, acknowledgedAmountUsd) have 0% schema description coverage and the description addresses none of them. The description's claim of no effect partially excuses this, but it leaves the agent unable to reconcile why a no-op tool accepts an idempotency key and a dollar amount.

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 states precisely what the tool would do (clear a do-not-disturb window) and immediately clarifies that the operation is a no-op because the call router does not read such a window. That is a specific, unambiguous purpose statement that lets an agent identify it as the counterpart to set_do_not_disturb, though it never names that sibling explicitly.

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?

'This tool is not yet supported' functions as an explicit when-not-to-use directive, which is the single most important routing signal here. It stops short of a 5 because it does not name the alternative an agent should call instead (e.g., set_do_not_disturb or get_my_profile) when a user asks about do-not-disturb settings.

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