Call Event

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

Adds behavior the annotations cannot express: the call is fire-and-forget, success only means the bus accepted the event, and no subscriber action is verified. It also documents a concrete failure mode and recovery (Claude Desktop 4-minute timeout, read the target back, delay manual approval) — genuinely operational context beyond readOnly/destructive/idempotent hints.

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 core action, then cleanly partitioned into when-not, when-to, and caveats. The Claude Desktop workaround paragraph is the longest block and is tangential to tool selection, but it is operationally useful rather than filler.

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?

An output schema exists, so return-value explanation is not required, and the description covers purpose, alternatives, and async caveats completely. The one gap is that destructiveHint=true is never reconciled with a tool that merely publishes an event — an agent cannot tell whether the destructiveness comes from the event itself or from downstream automations.

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% and both parameters (event_type, data) are fully documented in the schema itself, including how data surfaces as trigger.event.data. The description adds no format or syntax detail beyond that, so the baseline 3 applies.

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+resource ('Execute a custom event on the Home Assistant event bus') and immediately distinguishes itself from the two most confusable siblings by naming them (ha_call_service for entity control, ha_config_set_automation for running automations). An agent can select this tool without opening any 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?

Explicit 'When NOT to use' block names the alternatives and the condition that selects them, and the following paragraph gives the positive use case (event-triggered automations, Node-RED flows, custom integrations). Both when-not and when-to are covered, which is the top of the range.

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