mailkite_create_trigger

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

The annotations only state readOnlyHint, idempotentHint, and destructiveHint. The description adds valuable behavioral context: attaching never bumps the sequence version and never touches contacts already in flight, and it requires an API key. It does not describe response/error behavior, but it meaningfully supplements the sparse annotations.

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 action is front-loaded and the sentences are mostly purposeful. The 'fact about the outside world' metaphor is slightly decorative but helps justify why version bumps are irrelevant. There is no redundant restatement of the tool name or schema.

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 four parameters, including a rule-based filter, and no output schema. The description covers the core purpose and prerequisite but does not explain `filter`, `enabled`, or the expected response shape. It is adequate for a basic call but leaves gaps an agent would need to resolve.

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 coverage is only 50%, so the description needed to compensate for undocumented parameters. It explains `event` and indirectly `id`, but `filter` is entirely unexplained and `enabled` is only noted in the schema. For a tool with a rule reference, this leaves a significant semantic gap.

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 opens with a specific verb and resource: 'Attach a trigger', and clarifies the exact behavior: 'when this event arrives, enroll the contact it is about.' It also distinguishes triggers from sequences, helping an agent tell this apart from sibling sequence and trigger tools.

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?

It gives a concrete prerequisite: the sequence needs a `from` address before event-triggered enrollment, because there is no message to inherit a sender. It does not explicitly name alternatives or exclusion conditions, but the conceptual contrast with sequences and the prerequisite provide clear context for when to use it.

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