instances_stop_all

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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is known; the description adds genuinely new consequence information (traffic stops until instances restart) and timing (acts immediately). It stops short of stating auth requirements, whether it fails partially, or how recovery is triggered beyond the word "restart."

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?

Three short clauses, zero filler, with the blast radius and the outage consequence front-loaded before the alternative-tool pointer. 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?

With no parameters and no output schema, and annotations covering the safety profile, the description supplies what an agent actually needs: scope, consequence, and the sibling alternative. Slightly thin only on partial-failure behavior and how instances are restarted.

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 takes zero parameters, so there is no parameter meaning to convey and the baseline applies. The description correctly implies a global scope with no filtering options.

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 and resource with an explicit scope qualifier ("Stop every registered instance") and immediately contrasts it with the single-host sibling. An agent can distinguish this from instance_stop without opening any schema.

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?

Names the alternative explicitly ("Use instance_stop for one host") and pairs it with the condition that selects it. That is the only realistic branching decision for this tool family, and it is stated outright.

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