HubSpot MCP

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

With no annotations provided, the description carries full burden for behavioral disclosure. 'Update' implies mutation, but there's no information about permissions required, whether changes are reversible, validation specifics beyond the mention of 'validated properties', error handling, or what happens to unspecified properties. For a mutation tool with zero annotation coverage, this is inadequate.

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, efficient sentence that gets straight to the point. There's no wasted verbiage, though it could potentially benefit from being slightly more informative given the tool's complexity.

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 mutation tool with 2 parameters (one being a complex nested object), 0% schema description coverage, no annotations, and no output schema, the description is insufficient. It doesn't explain what happens during the update, what 'validated' means, what the response contains, or how this differs from similar sibling tools.

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%, so the description must compensate. It mentions 'validated properties' which hints at the 'properties' parameter, but doesn't explain what 'contactId' is, what validation entails, or provide any examples of valid property values. With 2 parameters (including a complex nested object) completely undocumented in the schema, the description adds minimal 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') and resource ('an existing contact'), making the purpose understandable. It specifies 'with validated properties' which adds some nuance. However, it doesn't distinguish this from sibling tools like crm_update_company or crm_update_lead, which have similar patterns.

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 provides no guidance on when to use this tool versus alternatives. With many sibling tools available (including crm_batch_update_contacts, crm_update_company, crm_update_lead), there's no indication of when this single-contact update is preferred over batch operations or when to use contact-specific versus generic object updates.

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