close_session

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

With no annotations, the description carries the full burden. It discloses the side effect of updating DailyActivity, which is valuable. However, it does not mention idempotency, error behavior when session already closed, or required permissions. This is a moderate level of transparency.

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?

Two sentences, front-loaded with the primary action, and the side effect in the second. No unnecessary words. Efficient and clear.

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?

The description covers the core action and side effect. The presence of an output schema means return values need not be described. However, it could be more complete about the nature of the DailyActivity update or potential failures, but it is adequate for a close operation.

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?

Schema coverage is 67% (session_id and ended_at described, actor_context not). The description adds no additional meaning beyond the schema's existing descriptions. It does not explain actor_context's purpose or how ended_at is used, leaving a gap for the agent.

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 main action ('Close a session'), the specific operation (update end timestamp), and a side effect (create/update DailyActivity). It distinguishes from sibling tools like delete_session (removes) and add_session (creates) by using 'close' and mentioning the specific resource and effect.

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 on when to use this tool versus alternatives. It does not explain prerequisites, why one would choose close over delete or update, or state conditions for appropriate use. The description only lists actions without contextual usage advice.

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