measure

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

Goes beyond the annotations by disclosing the real side effect: 'This switches the instrument (front panel included) to the given function,' which explains the non-read-only hint. It also lists return content and the accuracy caveat ('where the data sheet allows'), though it omits timing/duration expectations for slow vs fast modes.

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?

Front-loads the core action and follows with a clearly labeled Args block. The range enumeration is long but each entry is operationally necessary; a little redundancy remains in restating defaults already implied by the schema.

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 return-format explanation is optional, yet the description still names value, unit, range, timestamp and accuracy. All four parameters, the autorange default and the function-dependent interactions (speed validity, sensor requirement) are covered, leaving nothing needed to call it correctly.

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?

With 0% schema description coverage, the description carries the full load and does so: per-function valid range values, units (V, A, Ω, F), the autorange default when range is omitted, PLC semantics for speed with the slow default, and the requirement that sensor is mandatory for temperature.

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 and resource combination: 'Select a measurement function and take one reading.' The phrase 'one reading' implicitly distinguishes it from burst and sample, but it never names those siblings, so the agent must infer the split.

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?

Usage context is implied rather than stated: single-reading acquisition with defaults to autorange and slow speed. There is no explicit 'use burst/sample instead when you need multiple readings' routing, which matters given three nearby acquisition siblings.

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