Vehicle Database MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions that the decode is 'premium' and provides 'detailed specifications,' but does not disclose critical traits such as rate limits, authentication needs, error handling, or what happens with invalid VINs. The description adds some context about coverage and support, but lacks comprehensive behavioral details.

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 appropriately sized and front-loaded, starting with the core purpose. However, it includes some redundant phrasing (e.g., 'more than just a basic decode' could be more direct) and the sentences about coverage and support, while useful, could be integrated more smoothly.

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 tool's complexity (single parameter, no output schema, no annotations), the description is moderately complete. It covers the purpose, scope, and input requirements, but lacks details on output format, error cases, or performance characteristics. Without an output schema, more information on return values would be beneficial for full contextual understanding.

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%, with the parameter 'vin' documented in the schema as a string with an example. The description adds no additional meaning beyond the schema, such as format constraints or validation rules, but since the schema already covers the parameter adequately, the baseline score of 3 is appropriate.

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 tool's purpose: 'Premium VIN decode' that provides 'detail information about a vehicle including detailed specifications.' It specifies the verb ('decode') and resource ('vehicle information'), but does not explicitly differentiate from sibling tools like 'by_vin', 'decode_by_vin', or 'universal_vin_decode', which appear to offer similar functionality.

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 implies usage context by stating coverage for 'VIN from 1981-Present' and support for '17 digit VIN number,' which suggests when to use it (for VINs in that range and format). However, it does not explicitly state when to choose this tool over alternatives like 'by_vin' or 'decode_by_vin', nor does it provide exclusions or prerequisites.

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