Press a button entity

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

Annotations already declare readOnly=false, idempotent=false, destructive=false. The description adds real value beyond that: it discloses the underlying call (`button.press` with entity_id over HTTP) and the return payload ('list of states changed'). It does not mention permissions or side effects on the entity beyond its configured action.

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?

Front-loaded with the purpose, then the mechanism, then usage and return. Four short sentences, each doing work; the return note is slightly redundant given an output schema exists.

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 annotations covering the safety profile, a fully described single parameter, and an output schema, the description supplies enough context to invoke correctly. The only gap is the absence of explicit sibling alternatives.

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 description coverage is 100% with a single documented parameter, so the schema already carries full parameter meaning. The description repeats entity_id only via the call signature; baseline 3 is appropriate.

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?

States a specific verb and resource ('Press a button entity') and explains the effect ('running whatever action it is configured to perform'), which distinguishes it from siblings like entities_toggle or services_call_service. An agent can tell what this does without opening the schema.

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?

Provides a 'Use when' clause with concrete examples (template button, physical-button equivalent). It lacks explicit alternatives or when-not guidance (e.g., vs entities_toggle or generic services_call_service), so it stops short of the top tier.

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