entity_action

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

With no annotations, the description bears full burden. It discloses the action and return of response but omits side effects (e.g., state changes, error handling, permission needs). It adequately covers the basic behavior but lacks depth.

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, starting with purpose, then args, returns, examples, and domain parameters. It is front-loaded and organized, though somewhat lengthy; however, each section adds necessary value given the sparse schema.

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 3-parameter tool with no output schema, the description covers inputs thoroughly with examples and domain-specific info. It lacks details on output format or error cases, but overall it is sufficient for the tool's straightforward nature.

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?

Since the input schema has no descriptions (0% coverage), the description adds significant value: it explains entity_id and action, provides examples, and lists domain-specific parameters per entity type. This compensates well for the schema deficiency.

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 tool's purpose: perform standard actions (on, off, toggle) on Home Assistant entities. It specifies the verb 'perform an action' and resource 'entity', and distinguishes from siblings like call_service_tool by focusing on common actions.

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 through examples and domain-specific parameters but does not explicitly state when to use this tool versus alternatives like call_service_tool. No exclusions or prerequisites are provided, leaving the agent to infer appropriate context.

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