Create Contact

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

Without annotations, the description bears full burden for behavioral disclosure, but it only states 'create new contacts'—a tautology of the name. It does not mention authentication needs, error handling, idempotency (e.g., duplicate emails), rate limits, or any side effects. This is insufficient for an agent to understand the tool's behavior.

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 a single sentence, which is concise, but it is too minimal. It does not front-load any critical information beyond the name. Given that it could include key details like 'supports bulk creation' or 'email is required,' the brevity sacrifices completeness.

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 the tool's moderate complexity (array of objects, one required field), the lack of output schema, and missing annotations, the description should provide more contextual information, such as the fact that it accepts multiple contacts at once or what happens on failure. It fails to cover these aspects, leaving the agent underinformed.

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 provides descriptions for all properties (100% coverage), so the baseline is 3. The description adds nothing beyond stating 'create new contacts', which does not enhance understanding of the parameters or their usage. Thus, the score remains at the baseline.

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 'Create new contacts in your SendGrid account' clearly states the verb (create) and resource (contacts), distinguishing it from sibling tools like delete_contact or create_contact_with_lists. However, it does not explicitly contrast with similar create tools, so it's slightly shy of a 5.

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 like create_contact_with_lists or when to avoid it. The description lacks any context about prerequisites, limitations, or ideal use cases.

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