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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is structured data. The description does add non-obvious auth context ("Scope: sshkeys.write or vms.read"), which is the main value-add, but says nothing about return shape, ordering, or pagination for a listing call.

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?

Two short, front-loaded fragments with no filler – the resource comes first and the purpose follows. The telegraphic, comma-spliced style is slightly under-written, but nothing is wasted.

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 zero-parameter, no-output-schema listing tool with annotations covering safety and open-world behavior, the description supplies what structured fields cannot: the account-level scope and the required auth scopes. Only the return content/format is left unstated, a minor gap for such a simple read.

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 nothing the description needs to disambiguate; baseline for a no-param tool applies. No misleading parameter implications are introduced.

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?

"SSH keys saved on the account" identifies the resource clearly and, in combination with the name list_ssh_keys, makes the read-only listing intent unambiguous against siblings add_ssh_key and delete_ssh_key. It never states an explicit verb ("List"), so it falls just short of a precise verb+resource statement.

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?

"to pass to create_vm" gives a concrete downstream use case that tells an agent why and when to call this rather than another lookup. It stops short of explicit exclusions or naming alternative retrieval paths, so it is clear context rather than full when/when-not guidance.

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