create_key_event

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

With no annotations, the description must disclose side effects, but it only states the action without mentioning implications like whether this creates a new marking, modifies existing settings, or requires specific permissions. The mutation is implied but not elaborated.

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 two sentences, with the primary action front-loaded. It is appropriately concise, though the second sentence could arguably be integrated into the schema, but it remains useful in the description.

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?

The tool has 3 parameters, no output schema, and no annotations, so the description should provide more context. It does not explain what makes an event a 'key event', how counting methods differ, or what the response looks like. Minimal guidance for a create operation.

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 compensate. It adds value for counting_method by listing its possible values, but event_name and property_id are left unexplained. Their names are somewhat self-explanatory, but the description does not fully cover the parameters.

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 action ('Mark an event as a key event') and the resource (an event), with a parenthetical explaining 'conversion'. It is specific enough to understand the tool's core function, though it does not explicitly differentiate from siblings like list_key_events or create_event_audience.

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 guidance is provided on when to use this tool versus alternatives, nor any prerequisites or exclusions. The description only mentions the counting_method constraint, which is more about parameter usage than tool selection.

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