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

Annotations cover the safety profile (readOnlyHint=false, idempotentHint=true, openWorldHint=true, destructiveHint=false), and the description still adds substantial context: 'Spends nothing', the required permission (servers:update), the free-account requirement, the full consequence chain of HIBERNATE (12h window, hibernation fee, restart-then-delete) and DELETE (immediate, no fee, data lost). Notably it discloses the data-loss outcome even though destructiveHint=false, which is useful downstream context rather than a contradiction.

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 consequence semantics are front-loaded in a single dense sentence, and the trailing operational notes (cost, permission, account) are short. The HIBERNATE clause's nested parenthetical is heavy, but the overall length is proportionate to the behavioral detail being conveyed.

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 two-parameter, no-output-schema policy tool with full annotation coverage, the description supplies the trigger condition, per-enum consequences, hardware restriction, cost, and auth requirements. Nothing an agent needs to invoke this correctly is missing.

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 100%, so the baseline is 3, but the description goes further by defining what each enum value actually does to the server (retention window, fees, restart behavior, data loss), which the schema's bare 'HIBERNATE or DELETE' enum description does not convey. serverId is left to the schema, which is acceptable given the parenthetical reference to gpucloud_list_servers.

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 states a specific verb and resource ('What happens to an hourly server when the account balance reaches its threshold') and scopes it to hourly servers, clearly distinguishing it from siblings like gpucloud_hibernate_server, gpucloud_set_auto_reload, and gpucloud_set_budget. An agent can identify exactly what policy this tool configures without opening the 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?

It states the triggering context (balance reaches threshold and no automatic reload restores it) and a validity constraint (spot machines only accept DELETE). It does not explicitly name the sibling tools an agent should use for related balance/reload settings, so the alternative-selection guidance is implied rather than spelled out.

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