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

Annotations indicate readOnlyHint=false, idempotentHint=false, destructiveHint=false. The description expands on this by explaining that keep-alive consumes a per-account daily clock, that turning it off returns to the standard idle window, and that authentication is needed. No contradiction with annotations.

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 dense but every sentence earns its place. It is front-loaded with the core toggle function, then explains when to use it, then covers the clock and auth details. No fluff.

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 tool with 2 params, no output schema, and notable side effects (daily clock, auth), the description covers all essential information: the toggle behavior, usage conditions, plan limits, and the wallet_address requirement. Nothing critical is missing for correct invocation.

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 50% (only 'on' has a description). The tool description provides detailed semantics for 'on' (what true/false does) beyond the schema's brief line. It confirms wallet_address is required but doesn't add format or purpose details beyond that, so it doesn't fully compensate for the missing schema description, but it does add value.

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 it toggles KEEP-ALIVE on the user's session sandbox, with a specific verb and resource. It differentiates itself from sibling sandbox tools by focusing on keep-alive, and even references the chat twin of the SANDBOX pane control.

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?

It explicitly says 'USE THIS when the user asks to keep their sandbox alive / warm / persistent / from timing out, or to stop keeping it alive', and explains the on/true vs false behavior. It also notes paid-plan requirements, the daily clock, and that anonymous callers are told to log in.

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