Update HubSpot Contact

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

The description adds the important behavioral context that only provided fields are changed, which is beyond the idempotentHint annotation. It does not contradict annotations and provides useful transparency about partial updates.

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 extremely concise and well-structured: a clear first sentence, a clarifying second sentence, and a brief parameter list. No unnecessary words or redundancy.

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 two parameters and no output schema, the description adequately covers the update behavior. It could mention error handling or how to obtain contactId, but the core functionality is well explained.

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 coverage is 100%, so the description adds little beyond the schema. The Args section repeats parameter names and types without additional constraints or examples, offering minimal extra value.

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 (update), the resource (existing HubSpot contact), and a key behavioral trait (only provided fields are changed). It effectively distinguishes itself from sibling tools like create_contact or delete_contact.

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 does not explicitly state when to use this tool versus alternatives. It implies partial updates but lacks guidance on scenarios like when to use update vs. create. No exclusions or prerequisites are mentioned.

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