entity_action

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

With no annotations, the description should fully disclose behavior. It states this is a mutation action but omits important traits like idempotency, error states (e.g., entity not found), or authentication needs. The agent is left to infer these.

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: a clear summary sentence, then parameters, then domain-specific hints, then examples. It is front-loaded with the core action. The domain list could be trimmed, but each section is useful. No redundant information.

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?

Given no output schema and no annotations, the description should explain what the tool returns (e.g., success/failure, new state) and side effects. It does not, leaving a significant completeness gap. Examples show usage but not response. Agent cannot determine if the action succeeded or how to handle errors.

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?

Schema coverage is 0% (no descriptions in properties), so the description compensates well by explaining entity_id format, action values, and common domain-specific params for lights, covers, climate, and media players. Examples further clarify usage, adding significant meaning beyond the schema.

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 clearly states the verb ('Perform an action'), the resource ('Home Assistant entity'), and the specific actions (on, off, toggle). This distinguishes it from siblings like call_service (generic service calls) or get_entity (read-only), so purpose is unambiguous.

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 description implies usage for controlling entity state but does not explicitly differentiate from similar tools like call_service. No 'when-not-to-use' guidance or alternatives are mentioned, though the domain-specific hints indirectly help.

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