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

Annotations only carry destructiveHint=true, so the description usefully discloses that billing starts on boot and is metered hourly — a consequential behavioral fact the annotations do not convey. It still omits what happens on partial failure, auth/permission requirements, and the shape of the response, leaving some transparency burden unmet.

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 tight sentences with the billing warning front-loaded in caps immediately after the purpose, then prerequisites, then the API mapping. Every sentence earns its place and nothing is padded.

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 an 8-parameter mutation with nested objects and no output schema, the description covers the two things an agent most needs (cost implications and prerequisite lookups). It leaves the return value and failure modes unexplained, but the high schema coverage limits how much that matters.

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 100%, so all eight parameters (including nested labels and the ssh_keys fallback-to-emailed-root-password behavior) are already documented in the schema. The description adds no parameter-level detail beyond indirectly pointing at server_type pricing, so the baseline 3 applies.

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?

Names a specific verb and resource ('Provision a new server') and is instantly distinguishable from the read-side siblings like hetzner_get_server or hetzner_list_servers. It also states the underlying API mapping (POST /servers), removing any ambiguity about the operation being a 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 explicit prerequisite ordering: call hetzner_list_server_types for prices and hetzner_list_images for a bootable image before provisioning. It does not state when-not to use this tool (e.g. reusing an existing server), so it stops short of the full when/when-not/alternatives bar.

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