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

Annotations already declare idempotentHint=true and destructiveHint=false, but the description adds genuinely new behavioral detail: repeated closure returns the original closure state and does not delete contributions. This clarifies the idempotency and non-destructive semantics beyond what the structured hints convey.

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 tight sentences, front-loaded with the core action ('Immediately revoke...'), followed by return semantics and post-call guidance. No sentence is redundant.

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 usefully summarizes the return value (the closure event) and post-conditions (contributions preserved, token must be discarded). Nothing essential is missing for calling a zero-parameter tool whose safety profile is already carried by annotations.

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?

There are zero parameters (bearer is presumably supplied via auth context), so the baseline is 4. The description correctly ties the action to 'the supplied bearer' rather than a named argument, which is consistent with the empty schema.

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 a specific verb (revoke/close) and resource (the current revocable session bound to the supplied bearer), making the operation unambiguous. It does not need to name a sibling since no other tool closes a session, but it also gives no explicit contrast to alternatives.

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?

It provides post-call guidance ('discard the token; rejoin only to start a new session'), which implies the usage context. However it never states when to close a session versus keeping it active, nor names any alternative tool or exclusion, so guidance is implied rather than explicit.

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