createPerson

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

With no annotations, the description carries the transparency burden. It does disclose a non-obvious behavioral trait (custom fields as top-level 'custom'-prefixed keys) and directs to listCustomFields. It omits other important traits like duplicate-handling behavior (despite the deduplicate parameter), response shape, and permission requirements, so transparency is partial.

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?

Two sentences, front-loaded with the core action, followed by a high-value custom-field convention. No filler or repetition of schema details; every sentence contributes.

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 21-parameter creation tool with no annotations and no output schema, the description is minimal but not inadequate: the schema covers every parameter, and the custom-field note addresses a major gap. Still missing are the return value/created entity ID, duplicate behavior, and any minimal-input guidance, so it is only moderately complete.

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 schema already describes all 21 static parameters, so the baseline is 3. The description adds real value by explaining how to pass dynamic custom fields as top-level keys with a 'custom' prefix and by referencing listCustomFields for account-specific field names—information the schema cannot encode.

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 uses a specific verb and resource ('Create a new person/contact in FUB'), clearly distinguishing it from update/get/list person tools among siblings. The 'new' qualifier reinforces that this is for insertion, and the custom-fields note adds a relevant capability.

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 conveys a clear use case—new person/contact creation—and even instructs the agent to run listCustomFields for account-specific field names. However, it does not explicitly state when not to use it or mention alternatives such as updatePerson, bulkUpdatePeople, or checkDuplicate, leaving comparative guidance implied.

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