datastores

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

No annotations are provided, so the description carries the full behavioral burden. Listing read-only metrics (capacity, used, free, %) implicitly signals a non-mutating query, but it never states read-only behavior, permission requirements, or response shape explicitly.

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?

A single, densely packed sentence with the resource named first and the returned metrics listed after. No filler, though the run-on comma list is slightly harder to scan than a structured breakdown.

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 output schema, the field enumeration usefully tells the agent what comes back, which is the right compensation. However, with no annotations either, the description omits any behavioral or scoping context (read-only nature, coverage across hosts/clusters), leaving a gap for a monitoring tool.

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 per the rubric the baseline is 4. There is nothing for the description to disambiguate at the parameter level.

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 names a specific resource (datastores) and enumerates the exact data it surfaces — capacity, used, free, % usage, thin provisioning %, physical disk, and VMs. That field list clearly differentiates it from siblings like vms, snapshots, and host_info, though no explicit verb (list/retrieve) is stated.

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?

There is no when-to-use guidance, no prerequisites, and no mention of any alternative or sibling tool. The agent must infer that this is the tool for datastore capacity questions purely from the field list.

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