read_registers

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

readOnlyHint=true already tells the agent this is a safe read, and the description adds real behavioral context: values are scaled with units, and device_id resolves to the plant id (247) or the first configured device of that scope when omitted. It does not mention failure modes, invalid-name behavior, or batching/rate limits, so it is adequate but not rich.

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 one-line summary is front-loaded and followed by a tight three-item Args block. Minor redundancy with the schema's enum list, but every line carries information and nothing is padded.

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 readOnly/openWorld annotations and an output schema present, return values need not be described. All three parameters, the scope set, and the device resolution fallback are covered, leaving only error/degraded-read behavior unstated for a tool of this complexity.

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 0%, so the description carries the full burden and largely does: it gives example names, explains each scope enum value (e.g. 'plant (system level)'), and, most importantly, documents the device_id default resolution logic that the schema only shows as null. Only the array item typing and required-ness are left to 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 states a specific verb and resource (read named registers) and adds the outcome (scaled values with units), which distinguishes it from read_raw_registers. It also cross-references list_registers for name discovery. It stops short of explicitly contrasting itself with read_raw_registers, so it is clear but not fully sibling-differentiated.

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 parenthetical 'see list_registers' implies you must enumerate names first, which is useful routing guidance. However, there is no explicit statement of when to choose this over read_raw_registers or how scope selection relates to the sibling status tools (get_inverter_status, get_battery_status, etc.). Usage is implied rather than stated.

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