Databento MCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the tool 'Get only the metadata' which implies a read-only operation, but fails to detail aspects like error handling (e.g., invalid file paths), performance characteristics, or what metadata is included (e.g., file size, schema info). This leaves significant gaps for a tool with potential complexity.

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 front-loads the core purpose ('Get only the metadata from a DBN file') and adds a key constraint ('without reading all records'). There is no wasted wording, making it highly concise and well-structured for quick understanding.

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 one parameter and no output schema, the description is minimally adequate. It covers the basic purpose and scope but lacks details on return values (e.g., metadata structure), error cases, or integration with siblings like 'read_dbn_file'. Given the simplicity, it's complete enough to be functional but could be more informative.

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 input schema has 100% description coverage, with 'file_path' clearly documented. The description adds no additional parameter semantics beyond what the schema provides, such as format examples or constraints. Given the high schema coverage, a baseline score of 3 is appropriate as the description doesn't compensate but also doesn't detract.

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 ('Get') and resource ('metadata from a DBN file'), with the specific scope 'without reading all records' that distinguishes it from the sibling 'read_dbn_file'. However, it doesn't explicitly contrast with other metadata-related tools like 'get_symbol_metadata' or 'list_schemas', keeping it from a perfect 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 implies usage by specifying 'without reading all records', suggesting this tool is for lightweight metadata retrieval compared to full file reading. However, it lacks explicit guidance on when to use this over alternatives like 'get_symbol_metadata' or prerequisites such as file accessibility, leaving room for improvement.

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