hcl_backend_capabilities

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

The annotations already establish read-only, non-destructive, idempotent, and non-open-world behavior, so the description's added details are supplemental. It usefully clarifies that the tool never opens a socket and that its data comes from HCL's own logs rather than vendor documentation, which adds meaningful behavioral context.

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 only three short sentences and front-loads the core purpose. Every sentence adds value: the first states what is listed, the second states safety/offline behavior, and the third states data provenance.

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?

An output schema exists, so the description need not explain return values, and the annotations cover the safety profile. The description is nearly complete for a zero-parameter read-only capability-listing tool, though it could be stronger if it explicitly distinguished this tool from similarly named siblings.

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 are no parameter semantics for the description to explain. The baseline for a parameterless tool is 4, and the description does not create any parameter-related confusion.

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 uses a specific verb and resource: it lists observed backend verbs with their evidence level and gating state. That is clear enough to distinguish the tool's basic function, but it does not explicitly differentiate it from sibling tools such as hcl_capabilities or hcl_backend_topology.

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?

It gives useful context for when this tool is appropriate: it is read-only and offline, and it reports observed backend verbs from HCL logs rather than vendor documentation. It does not name an alternative or explicitly say when not to use it, but the source/provenance distinction provides clear usage guidance.

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