Hvac update air handler

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

Annotations already declare non-read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds only 'existing', and omits partial-update semantics (whether unspecified properties are left unchanged) and behavior when the ID is invalid or absent.

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 short sentence with the verb and resource front-loaded and no filler. It is efficient, though its brevity reflects under-specification rather than a considered minimum.

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 annotations covering safety and a fully documented schema, the core is adequate for a simple partial-update tool with no output schema. It still leaves gaps around partial-update semantics and error behavior for missing units.

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 description coverage is 100%, so the schema fully documents id, fanType, maxAirflowCFM, and staticPressurePa including the enum-like fan type values. The description adds no parameter meaning beyond that, so the baseline of 3 applies.

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?

States a specific verb ('Update') and resource ('properties of an existing air handler unit'), which is clearly distinguishable from hvac_add_air_handler and hvac_remove_air_handler by operation. However, it does not name or reference the related sibling tools (hvac_update_duct, hvac_update_node) to reinforce the boundary.

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 guidance on when to use this versus alternatives or prerequisites. The word 'existing' hints the unit must already exist, but there is no explicit when-to-use or when-not-to-use statement.

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