create_contact

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

No annotations are provided, so the description carries the full burden. It discloses that creating a contact can trigger automations (e.g., enrollment in a course or campaign), which is a significant side effect. However, it does not disclose whether duplicate emails are allowed, permission requirements, rate limits, or what the response contains.

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 no extraneous information. It front-loads the core action and then adds the key behavioral note about automations. Every word earns its place.

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?

For a tool with 3 parameters, no output schema, and no annotations, the description covers the purpose, inputs, and side effects. However, it lacks guidance on what the function returns (e.g., contact ID) and does not address duplicate handling or prerequisites. It is adequate but not thorough.

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?

The input schema has 100% coverage, with each parameter described. The description echoes the schema (email required, optional locale and custom fields) but adds no new meaning beyond summarizing it. The baseline of 3 is appropriate as the schema already does the heavy lifting.

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 (create), the resource (contact in Systeme.io), and the required input (email address) with optional fields. It distinguishes from sibling tools like update_contact or delete_contact by focusing on creation and noting that it can trigger automations, which is unique to creation.

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 implies use when you need to add a new contact, but it does not explicitly state when to use this tool versus alternatives like update_contact or enroll_contact_in_course. No exclusions or prerequisites are mentioned, leaving the agent to infer usage context.

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