Create a HubSpot contact using a Private App access token, with optional email and properties, to add contact records from automated workflows.
Create a HubSpot contact.
| Name | Required | Description | Default |
|---|---|---|---|
| No | Contact email address | ||
| properties | No | Additional contact properties (firstname, lastname, company, phone, ...) | |
| access_token | Yes | HubSpot Private App access token |
Changes observed during successful MCP inspections.
v0.1.11Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It says nothing about whether duplicate emails error or upsert, whether the operation is idempotent, what permissions/scopes are required, or what gets created. For a mutation tool with zero annotation coverage this is a significant gap.
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 single sentence is front-loaded and wastes no words, which is appropriate. It is efficient but comes at the cost of under-specification rather than being genuinely structured.
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 no annotations, no output schema, and a nested properties object, one sentence is inadequate. Key facts an agent needs (idempotency, duplicate handling, required scopes, response shape) are all absent.
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 email, properties, and access_token are all documented in the schema, and the baseline is 3. The description adds no syntax, format, or usage detail for the nested properties object beyond what the schema already says.
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 verb (Create) and resource (HubSpot contact) that an agent can immediately understand. It does not explicitly differentiate from siblings like hubspot_get_contact or hubspot_search_contacts, but the create-vs-read distinction is clear from the verb.
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?
There is no guidance on when to use this tool versus hubspot_search_contacts or hubspot_list_contacts, no mention of prerequisites (an access token is required but unexplained), and no conditions or exclusions. The agent gets no routing help beyond the verb.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.