upsert_contact

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the mutation but does not explain how upsert determines existing records, whether partial updates merge or overwrite omitted fields, or whether api_token is required. This is a significant gap for an upsert operation.

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 concise sentence that is front-loaded, but it is under-specified for a tool with six parameters and an upsert behavior. It earns its place but leaves the reader needing much more information.

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?

Although an output schema exists, the description is inadequate for a 6-parameter mutation tool with no annotations. It does not cover upsert semantics, authentication via api_token, or behavior with respect to optional fields, making it incomplete in context.

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%, and the description adds no parameter information. While some parameter names like 'email' and 'name' are self-explanatory, others like 'api_token' and 'links' are ambiguous and the description does not compensate for the lack of schema-level descriptions.

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 verb 'Create or update' with resource 'contact', which is specific and distinguishes it from read-only sibling tools like find_contact_by_email. However, it does not mention that the email field is the unique key determining whether a create or update occurs, leaving some ambiguity.

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, such as find_contact_by_email for looking up contacts or create_label for label management. There is no mention of appropriate scenarios or exclusions.

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