end_session

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

With no annotations, the description carries the burden of disclosing side effects and state changes. It only states the action and that it returns a confirmation, but does not explain whether ending a session is destructive, reversible, or requires an existing session. This is a significant gap for a state-changing tool.

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 core sentence is concise and front-loaded, but the docstring formatting with Args/Returns adds a bit of redundancy. It is still well-structured and every sentence contributes meaning.

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 the tool's simplicity (one optional parameter and a simple confirmation return), the description covers the basic purpose and parameter semantics. However, it lacks usage context and behavioral details, making it minimally viable but not 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?

Although the schema coverage signal is 0%, the description itself includes an Args section explaining `summary` as "Brief summary of what happened in the session." This adds meaning beyond the schema's default empty string, making the single parameter's purpose clear.

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 ("End") and a clear resource ("the current session"), which clearly distinguishes it from siblings like `start_session` and `shutdown`. The action is unambiguous: ending an active 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?

No guidance is provided on when to use this tool versus alternatives like `start_session` or `shutdown`. The description does not mention any prerequisites (e.g., an active session) or contrast with lifecycle siblings, so an agent gets no context for tool selection.

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