call_service_tool

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

With no annotations, the description should fully disclose behavioral traits. It describes the return format and shows service examples (turn_on, reload) that imply state changes, but does not explicitly state that calls can be destructive, require permissions, or have side effects. The 'low-level' warning partially compensates.

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 concise and well-structured with sections for args, returns, and examples. Every sentence adds value, no redundancy.

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?

Covers purpose, parameters, return format, and examples. However, missing behavioral context (destructive potential, permissions) and usage guidelines given the generic nature of the tool. The output schema exists but return description is adequate.

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 0%, so the description must fully explain parameters. It provides examples but no additional semantics: no allowed domain values, no service validation, no details on data structure beyond a single example. The description adds minimal value beyond the schema field names.

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?

Clearly states 'Call any Home Assistant service (low-level API access)' with a specific verb ('Call') and resource ('Home Assistant service'). The low-level designation distinguishes it from sibling tools like entity_action or domain_summary_tool.

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?

No explicit guidance on when to use this tool versus alternatives. The description mentions 'low-level API access' implying direct use, but does not specify when not to use it or name alternative tools for common cases (e.g., entity_action for entity control, list_entities for discovery).

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