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

Annotations already mark destructiveHint=true and idempotentHint=true. The description goes further by revealing the cascading destructive behavior ('all its entries/sets') and the boolean return value, which is not visible in annotations. This is valuable beyond the structured hints.

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?

The description is a single front-loaded sentence stating the action, its scope, and the return value. No filler words or restatement of the title.

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 one-parameter destructive tool with output schema and safety annotations, the description covers the key behavior (cascading delete) and return shape. However, it omits edge behavior (e.g., non-existent session) and there is no parameter guidance, so it is not fully complete.

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?

The only parameter, session_id, has no description in the schema and 0% coverage. The description does not mention session_id at all, leaving the agent to infer its meaning solely from the parameter name. This fails to compensate for the missing schema documentation.

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 uses the specific verb 'Delete' with the resource 'session' and explicitly notes the cascading scope 'and all its entries/sets'. This differentiates it from sibling tools like update_session, log_session, and get_session.

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?

The description implies its use case—deleting a session—but provides no explicit when-to-use guidance or mention of alternatives such as update_session or get_session. The agent must infer applicability from the tool name and title.

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