HubSpot MCP Server

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

With no annotations provided, the description carries full burden but only states it's an update operation. It doesn't disclose critical behavioral traits: whether this is a mutation (implied but not explicit), permission requirements, rate limits, error handling, or what happens to contacts not in the updates array. For a batch mutation tool, 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 description is a single, efficient sentence with zero wasted words. It's appropriately sized and front-loaded with the core action, making it easy to parse quickly.

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 batch mutation tool with 2 parameters (including a complex nested array), 0% schema coverage, no annotations, and no output schema, the description is incomplete. It lacks information on behavior, parameters, outcomes, and error cases, leaving the agent under-informed about this potentially impactful operation.

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 but adds no parameter information. It doesn't explain what 'subscriptionId' refers to, the structure of 'updates' array, or the meaning of enum values like 'SUBSCRIBED' or 'LEGITIMATE_INTEREST_CLIENT'. This leaves parameters semantically undocumented.

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 'Update subscription status for multiple contacts' clearly states the verb ('Update'), resource ('subscription status'), and scope ('multiple contacts'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'communications_subscribe_contact' or 'communications_unsubscribe_contact' which handle individual contacts, so it doesn't reach the highest score.

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. It doesn't mention prerequisites (e.g., needing subscriptionId), compare to single-contact tools like 'communications_subscribe_contact', or specify use cases like batch updates. This leaves the agent without contextual direction.

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