Simulate failover invariants

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable context beyond annotations by specifying 'isolated deterministic simulation' and explicitly reinforcing 'No live proxy is changed'. This discloses determinism and isolation, which are not apparent from annotations alone.

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 two sentences, front-loaded with the main action. The second sentence provides essential safety context without redundancy. Every word contributes to understanding the tool's purpose and behavior, achieving maximum conciseness.

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?

With no parameters, rich annotations, and an output schema, the description is complete. It enumerates the specific areas simulated (adaptive failure gates, timing, connection preservation, ranking) and explicitly states the no-live-change guarantee. There is no missing critical context for an agent to select and invoke this tool correctly.

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 zero parameters, so the baseline score is 4. The description has no need to explain parameter semantics; the empty schema and description coverage are consistent. No additional parameter information is required.

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 action: 'Run an isolated deterministic simulation' with a specific resource domain (adaptive failure gates, prepared-route timing, connection preservation, distinct-exit ranking). This distinguishes it from siblings like install_failover or start_monitor, which represent actual live changes.

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 provides clear context and implied usage: it is a simulation and 'No live proxy is changed', so it is safe for testing failover behavior without affecting production. However, it does not explicitly name alternative tools or state when not to use it, missing the highest bar for explicit guidance.

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