system_overview

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

No annotations are provided, so the description carries the full burden. It explains the return structure in detail (dictionary with keys) and notes that area distribution is included 'if available'. While it doesn't disclose any side effects or performance implications, for a read-only overview tool this is adequate; a slight deduction for not noting potential size or latency.

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 well-structured with Returns, Examples, and Best Practices sections, and it is appropriately sized for the complexity. It is not overly verbose, but the 'Examples' line is redundant with the 'Returns' section, which costs one point.

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?

The tool has no parameters and an output schema is present, so the description's role is largely to explain the output semantics and usage context. It does both excellently: it enumerates all returned fields and gives clear guidance on when to use it. The output schema covers the structure, and the description adds the 'if available' nuance and the workflow suggestion.

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 tool has zero parameters, so there are no param semantics to document. The description adds value by explaining the return structure, which the input schema cannot do. Baseline for 0 params is 4, and the description fully compensates by detailing what the output contains.

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 starts with a clear verb and resource: 'Get a comprehensive overview of the entire Home Assistant system.' It distinguishes from siblings by explicitly positioning it as the first call for exploration, and it lists the returned fields, making the 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 Best Practices section explicitly says to use it as the first call when exploring an unfamiliar instance and to then use domain_summary_tool for deeper dives. However, it doesn't explicitly state when not to use it or name alternatives beyond domain_summary_tool, though the context is clear.

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