get_hydrometer

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

With no annotations provided, the description carries the burden of transparency. It does list the specific fields returned (gravity, velocity, temperature, battery), which is useful. However, it does not disclose any error behavior (e.g., not found), rate limits, or whether readings are live/cached, leaving clear gaps.

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 description is a single, front-loaded sentence that immediately states what the tool does and lists the key return fields. There is no filler, repetition, or unnecessary detail.

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 simple single-parameter get tool with no output schema, the description adequately covers the purpose and the main return values. It is not overly verbose, but it is sufficiently complete for an agent to understand what the tool provides.

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?

The schema covers the single parameter 'hydrometer_id' with a description ('UUID of the hydrometer/RaptPill'), achieving 100% schema description coverage. The tool description adds minimal semantic value beyond restating that it's for a single hydrometer, so the baseline of 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 uses a specific verb ('Get') and resource ('detailed status of a single RaptPill hydrometer'), clearly distinguishing it from the plural sibling 'get_hydrometers'. It also enumerates the key data points returned, making the tool's purpose unmistakable.

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 word 'single' clearly implies this tool is for one hydrometer, contrasting with the plural 'get_hydrometers'. It provides clear context for when to use it, but does not explicitly mention alternatives like 'get_hydrometer_telemetry' or state when not to use it.

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