contactUpdate

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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It only says 'Update an existing contact profile' and does not mention whether it performs a partial or full replacement, validation rules, authentication needs, side effects, or response format. The external API reference link is not sufficient inline context.

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 clear, front-loaded sentence with a reference link and no wasted words. It is concise, though it could have used its length to include more usage or behavioral context.

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?

This is a complex mutation tool with 19 parameters, 10 required fields, no output schema, and no annotations. The description is minimal and does not cover behavior, response expectations, or selection guidance, making it insufficient for an agent to confidently call the tool correctly without external lookups.

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 100%, so every parameter already has a clear description. The tool description adds no additional parameter meaning, but the schema carries the workload, so a baseline ​3 is appropriate.

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 states a specific action ('Update') and a specific resource ('existing contact profile'), and the word 'existing' helps distinguish this from contactAdd and contactDelete. However, it doesn't explicitly enumerate what fields can be updated, relying on the schema for that.

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 given on when to use this tool versus contactAdd, contactDelete, or contactDomainAssociate. The 'existing' phrasing implies it is for already-created contacts, but no explicit context or exclusions are provided.

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