end_session

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

The description discloses that the tool ends the session and returns a summary, but does not mention side effects such as whether the session is permanently ended, if data is saved, or if it can be undone. No annotations are provided to compensate.

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 concise with two short sentences that convey the essential action and return value. No extraneous 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?

While the tool has an output schema (not shown) reducing the need to explain returns, the description lacks context on prerequisites (e.g., must have an active session), consequences (e.g., irreversible), and error states. Given the simplicity, it is adequate but not thorough.

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 tool has no parameters, and the input schema coverage is 100% trivially. Per the rubric, 0 parameters baseline is 4. The description does not need to add parameter meaning since none exist.

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 clearly states the tool ends the current active session and returns a summary. It distinguishes from sibling tools like pause_session (which suspends) and next_phase (which advances), making its purpose unambiguous.

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 does not provide explicit guidance on when to use this tool versus alternatives like pause_session or resume_session. The usage is implied by the name and description, but no when-not-to-use or context of alternatives is given.

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