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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description still adds real value beyond them by stating the status is 'authoritative' and by disclosing the auth model — the lease capability comes from the transport and is never an argument or response field, which preempts an agent trying to pass a credential.

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 sentences with zero padding; the core action is front-loaded and the second sentence carries a distinct, non-redundant constraint.

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?

An output schema exists, so return-value detail is not required, and the description names the returned fields (status, expiry). For a single-parameter read tool this is nearly complete; only usage/routing guidance is absent.

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%, so the description must compensate, and it only partially does: it clarifies what is NOT a parameter (the lease capability) but never explains the single session_id beyond the schema's regex pattern. With one parameter and a credential-related clarification, this is roughly baseline.

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 ('Return') and resource ('status and expiry for one browser-session lease'), which is enough to distinguish it from the mutating siblings ausca_browser_session_close and ausca_browser_session_connect. It stops short of naming those alternatives explicitly, so sibling differentiation is implied rather than stated.

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?

There is no when-to-use or when-not-to-use guidance, and no routing to alternatives such as ausca_lease_browser or ausca_browser_session_close. An agent must infer that this is the read path for an existing lease purely from the name.

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