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

Despite no annotations, the description reveals critical behavior: it reports the cancellation policy tier but does NOT create any charge or persist a penalty. This clearly sets expectations for side effects. A minor gap is not mentioning whether the session could be in cancelable state (e.g., already cancelled), but overall transparency is strong.

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?

Every sentence provides unique value: protocol lane, state change, event emission, policy reporting, no charge distinction, sibling alternative, and a requirement. No filler or repetition. The most important behavioral notes are 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?

Given no output schema and no annotations, the description does most of the heavy lifting. It covers purpose, side effects, alternatives, and a key requirement. A slight gap is not describing return values (e.g., should it return the policy_applied field?), but no output schema is declared, so this is a minor omission. Overall, well-rounded for a cancellation tool among many siblings.

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 coverage is 0%, so description must compensate. It mentions 'confirm: true' needs to be passed, implying the confirm parameter's purpose, but does not explain apiKey, reason, orgSlug, or session_id. The description does add the requirement for X-Org-Api-Key (not in schema), but overall only partially covers 5 parameters. Baseline 3 is appropriate for this incomplete compensation.

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 clearly states it cancels a session through a specific protocol lane. It includes concrete details: it moves the session to cancelled state, emits an event, and explicitly contrasts itself with the sibling booking_cancel, which makes the purpose and distinct role 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?

Provides explicit when-to-use guidance by naming the sibling alternative (booking_cancel) that should be used 'if you need the organization lane that actually applies the policy and registers the charge.' Also states a requirement for 'confirm: true and X-Org-Api-Key', which clarifies invocation context.

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