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

Annotations already declare destructiveHint=true, so the agent knows this is a mutating action. The description adds the useful side effect that the slot is freed for the user's IP, but does not cover idempotency, error behavior on invalid/expired sessions, or whether the action is reversible.

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 short sentences, no waste, front-loaded with the primary action and the timing constraint. Every sentence earns its place.

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 no output schema, the description gives adequate purpose and side-effect context. However, it leaves the required sessionId's provenance and error/edge-case behavior undocumented, which an agent would want before invoking a destructive call.

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 description coverage is 0% and the single required sessionId has no description in either schema or description text. The description does not explain where sessionId comes from (e.g. from sandbox_create_session or sandbox_list_sessions) or its expected format beyond the uuid type in the schema.

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?

States a specific verb (End) and resource (sandbox session) plus the key behavioral nuance: terminate now rather than waiting for expiry. This clearly distinguishes it from the read-only sibling sandbox_get_session and from session creation.

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?

Gives clear context: use when you want to end a session immediately instead of letting it expire. It implies the alternative (wait for expiration) but does not name a sibling tool or state exclusions (e.g. what happens on already-expired sessions).

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