read_sensor_relative

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

Annotations already declare the operation read-only and non-destructive. The description adds the important behavioral dependency that readings are deltas from a prior zero reference. It does not describe the error case if no reference has been captured, but core behavior is sufficiently transparent for this simple read.

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, front-loaded sentence that states the operation and the key precondition without filler. Every word contributes to the tool's meaning.

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?

For a two-parameter, read-only tool with no output schema, the description gives the essential purpose and dependency. It omits an explicit pointer to zero_sensor_reference and the return format, but neither is critical given the operation's simplicity.

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%, and the description does not explain the port or sensor_type parameters; it only references 'sensor zero reference' in a general way. The enum values are self-explanatory, but the description does not compensate for the missing schema descriptions.

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 ('Read') and a specific resource ('change from a previously captured sensor zero reference'). It clearly differentiates from sibling read_sensor and read_sensor_raw by centering on a relative measurement rather than an absolute or raw reading.

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 phrase 'previously captured sensor zero reference' implies the tool should be used after zero_sensor_reference has been run, but it does not explicitly state when to prefer this tool over read_sensor or read_sensor_raw, nor does it mention exclusions.

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