ha_history_list_devices

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

With no annotations, the description carries full burden. It clearly indicates a read-only listing operation and describes output as analytics-ready entity_ids. It could be more explicit about side-effect-free nature, but the behavior is transparent enough for a list operation.

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 three sentences, front-loaded with purpose, and every sentence adds value: what it does, how to use it, and what to do with results. 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?

Given no output schema, the description appropriately explains return values (devices with entity_ids) and provides cross-tool context. It covers the main use cases and directs to related tools, making it complete for a list/filter tool.

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%, so baseline is 3. The description adds marginal semantic context for area and search (room-based vs device lookup), but does not significantly elaborate beyond the schema's parameter descriptions.

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 lists devices in Home, with filtering by area or search. It also distinguishes itself from related tools by explicitly directing use of the returned entity_ids with analytics tools and telling when to call ha_history_list_device_entities instead.

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 provides explicit usage guidance: use area for room-based discovery and search for device/appliance lookup. It also gives clear direction on when to use this tool versus ha_history_list_device_entities, and advises using returned entity_ids with analytics tools.

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