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

Annotations already establish the safe read-only, non-destructive, closed-world profile, so the description's remaining job is to add context. It does indicate the response covers liveness state, a departure reason, and a cost figure, which is useful signal about what the call surfaces. However, it leaves unclear whether the record is a live or historical session and says nothing about auth or permissions.

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?

It is a single short sentence with no filler, which is structurally appropriate for a simple getter. The problem is that the compression comes at the cost of intelligibility: metaphor substitutes for specification.

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 values need not be explained, and the tool is simple with one parameter. Even so, the description fails on the one thing it uniquely had to supply — what the id is and what distinguishes this read from get_nod and the session lifecycle 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?

There is one required parameter with zero schema description coverage, and the description never mentions what the 'id' identifies — session id versus Nod id is genuinely ambiguous given the Nod-centric wording. This is exactly the case where the description needed to compensate for the schema gap and does not.

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 is a metaphorical list of returned facts ("whether the Nod is still in the room, why it left, and what it cost") rather than a statement of what the tool does. It contains no verb and never says it reads or retrieves a session record, so the agent must infer the purpose from the name alone. It is also at odds with the title's framing of a 'live' session while describing post-settlement cost.

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 guidance and no reference to alternatives such as get_nod, start_session, or stop_session, even though several siblings operate on the same objects. The phrase 'once settled' faintly implies post-session retrieval but not enough to route an agent reliably.

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