Check configuration validity

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety and repeat-safety profile is fully covered structurally. The description adds the underlying REST endpoint and the lifecycle point at which to call it, but says nothing about duration, whether it reloads anything, or how the check result is reported. Useful context, not rich behavioral detail.

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?

Two short sentences, no filler, with the what in front and the when second. Every clause earns its place, including the endpoint which is genuinely load-bearing for anyone cross-referencing HA docs.

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?

With no parameters and no output schema, the description carries the burden of describing the return shape, and it does not: an agent cannot tell whether this yields a boolean, a list of config errors, or just a log excerpt. It is otherwise complete for a zero-arg check tool, but that return-value gap matters when the entire point is reading the outcome.

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 takes zero parameters, so there is nothing for the description to disambiguate; per the stated baseline this is a 4. The description correctly implies no inputs are required and adds no confusing parameter talk.

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 names a specific verb and resource ('Run Home Assistant's configuration check') and even cites the backing endpoint POST /api/config/core/check_config, so the action is unambiguous. It does not explicitly distinguish itself from siblings like validate_automation_config or validate_script_config, which is the only thing keeping it off a 5.

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?

'Use before and after any change to YAML or storage config' gives concrete triggering conditions, which is more than most tools offer. It stops short of naming alternatives (the narrower validators) or when not to run it, so it is clear context without exclusions.

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