datastore_capacity

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

Beyond annotations (readOnlyHint, etc.), the description explains that it returns specific fields (capacity_gb, free_gb, committed_gb, provisioned_gb, used_pct, overcommit_pct), orders riskiest first, is point-in-time, and clarifies the meaning of overcommit >100%.

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 description is concise, front-loaded with the READ tag and purpose, followed by a clear explanation, return fields, and parameter list. Every sentence adds value without redundancy.

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?

Given the tool's simplicity (2 optional params, output schema exists), the description covers all necessary aspects: purpose, behavior, parameters, return fields, and differentiation from sibling. It is fully adequate for an agent to use correctly.

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 0% schema description coverage, the description fully explains both parameters: target (optional, uses default) and limit (optional, None=all). This adds essential meaning beyond the schema.

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 clearly states the tool returns per-datastore capacity with thin-provisioning over-commit, and explicitly differentiates itself from the sibling tool list_all_datastores by adding the overcommit_pct risk signal.

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 description implies when to use this tool (when overcommit risk is needed) and contrasts with list_all_datastores, but does not explicitly state when not to use it or provide multiple alternatives.

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