Get hub variable

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

Annotations already cover readOnly=True, idempotent=True, destructive=False, and openWorld=True. The description adds value beyond these by noting this is an admin route and firmware-sensitive, giving context about access level and stability that the annotations don't convey.

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?

Compact and well-structured with clear sections. Every sentence earns its place — no filler, no redundancy. The use-when/not-use-when breakdown is front-loaded and efficient.

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 single-parameter read tool with a rich annotation set (readOnly, idempotent, openWorld) and an output schema. The description covers the main use case and exclusion. The admin/firmware warning adds important context. Slightly more on return format could push it to 5, but this is nearly complete for a simple read 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?

Schema coverage is 100%, so the schema documents the single 'name' parameter. The description implies it's the hub variable name but adds no format/syntax details beyond the schema's own 'Hub variable name' description. Baseline 3 is appropriate.

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 'Read a Hubitat hub variable' — a specific verb (read) + resource (hub variable), and distinguishes from the sibling tool hubitat_set_hub_variable and from device attributes via hubitat_get_device. The admin-route and firmware-sensitive qualifiers add useful context.

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?

Explicit 'Use when' and 'Do NOT use when' sections with a named alternative (hubitat_get_device for device attributes). This explicitly differentiates from siblings and clarifies when the tool is and isn't appropriate.

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