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

With no annotations, the description carries the full behavioral burden. It discloses that the session is closed and summarizes the report contents, but it omits whether closure is irreversible, what happens to in-flight operations, permission requirements, or error behavior for a likely mutating action.

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 efficient sentence with the action front-loaded and the return contents following immediately. Every clause contributes useful information.

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 simple one-parameter tool with full schema coverage, the description adequately covers the action and the report fields. However, without annotations or an output schema, it should do more to explain session-ending side effects and lifecycle implications.

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 only one parameter, and the schema fully documents it as 'Session from open_app'. The description does not add further meaning beyond the schema, so the high schema coverage supports a baseline score of 3.

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 a specific verb and resource ('Close the session') and adds the resulting report contents. It is clear what the tool does, though it does not explicitly differentiate itself from siblings such as open_app or list_sessions.

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 phrase 'Close the session' implies this should be used when ending a session, and the schema notes the session comes from open_app. However, the description itself gives no explicit when-to-use guidance, exclusions, or alternatives.

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