Vercel 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. 'Lists deployments' implies a read-only operation but doesn't specify whether this requires authentication, what format the output takes, whether results are paginated, or any rate limits. For a tool with 12 parameters and no annotation coverage, this minimal description leaves critical behavioral aspects undocumented.

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 maximally concise at just two words, with zero wasted language. While this conciseness comes at the expense of completeness, the description is perfectly structured and front-loaded with the core action.

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 tool with 12 parameters, no annotations, no output schema, and multiple sibling tools, the description is severely incomplete. It doesn't explain the relationship between similar parameters (like 'from/to' vs 'since/until'), doesn't indicate typical use cases, and provides no information about the return format or error conditions.

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?

The schema description coverage is 100%, with all 12 parameters clearly documented in the input schema. The description adds no parameter information beyond what's already in the schema, so it meets the baseline score of 3 for high schema coverage. However, it doesn't provide any higher-level guidance about parameter relationships or typical usage patterns.

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 'Lists deployments' is a tautology that essentially restates the tool name 'getDeployments' without adding meaningful specificity. While it correctly identifies the verb ('Lists') and resource ('deployments'), it fails to distinguish this tool from its sibling 'getDeployment' (singular) or provide any scope information about what kind of deployments are listed.

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 absolutely no guidance on when to use this tool versus alternatives. With sibling tools like 'getDeployment' (singular), 'cancelDeployment', and 'deleteDeployment', there's no indication that this tool lists multiple deployments while 'getDeployment' retrieves a specific one, or when filtering vs. direct retrieval is appropriate.

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