get_battery_soc

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

With no annotations present, the description carries the behavioral disclosure burden and does a good job by revealing the dual-mode output behavior for instance=0 versus instance=N. It does not mention error cases or units, but it makes the core conditional behavior visible beyond what the simple schema shows.

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 two sentences with no filler: the purpose is front-loaded and the parameter behavior is stated compactly. Every word contributes to either identification or correct invocation.

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 one-parameter getter with an output schema, the description covers the key behavioral branch and parameter interpretation. It lacks only minor context such as source of the instance index or behavior when no devices are found, but these are not critical given the output schema and simple interface.

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 input schema provides only an integer parameter with a default and no description, so schema coverage is 0%. The description fully compensates by explaining that 0 aggregates all batteries under 'readings' and non-zero values select a single device dict, giving the parameter meaning beyond its type and default.

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 opens with a specific verb and resource, 'Get battery state of charge,' which uniquely identifies this read operation among getters like get_pv_power and get_grid_status. It also clarifies that instance=0 returns all discovered batteries while instance=N returns a single device, adding scope and removing ambiguity.

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 by the resource name and first sentence: the agent should call this when it needs battery state-of-charge data. However, there is no explicit guidance about when to prefer this over list_devices or how to choose a valid instance value, and no exclusions or alternatives are named.

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