hcloud_update_image

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

Annotations already declare destructiveHint=true and openWorldHint=true, so the safety profile is covered. The description adds the useful eligibility constraint, but it omits the operationally important detail that supplied labels overwrite the entire existing label set (that warning lives only in the nested schema) and says nothing about irreversibility of the backup-to-snapshot conversion.

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?

Short and front-loaded with the action, then the mutable fields, then the constraint. Minor waste in the opening redundancy ('Update an Image' followed by 'Updates the Image'), which repeats the same information twice.

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?

A two-parameter tool (one nested body) with no output schema and annotations covering safety; the description names all mutable fields and the type restriction, which is most of what an agent needs. The remaining gap is the overwrite semantics of labels, which is documented in the schema but not surfaced in the description.

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?

With 50% schema description coverage, the description compensates well: it explains that `type` is a conversion from backup to snapshot (the schema only says 'Destination Image type to convert to') and that description/labels are the other mutable fields. It does not clarify the label-overwrite semantics or that `id` must reference an existing updatable Image.

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 (update an Image) and immediately enumerates the three mutable aspects: description, backup-to-snapshot conversion, and labels. It also states the hard eligibility constraint that only snapshot and backup Images can be updated, which lets an agent distinguish this from get_image, list_images, or image action tools.

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 eligibility rule ('Only Images of type `snapshot` and `backup` can be updated') is a concrete precondition an agent can check before invoking, and the enumeration of changeable fields implies scope. It does not, however, reference any sibling tool (e.g., use hcloud_get_image first to confirm the type), so routing context is only implied.

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