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 implies a read-only operation ('Get') and describes return values, but lacks details on permissions, rate limits, or side effects (e.g., the reset parameter's impact). The example hints at reset behavior, but this is covered in the schema description.

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 well-structured and appropriately sized. It front-loads the core purpose, uses bullet points for returns efficiently, and includes a concise example. Every sentence adds value without redundancy, making it easy to scan and understand.

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 no annotations and no output schema, the description partially compensates by listing return values, but it lacks details on behavioral traits (e.g., side effects, permissions). For a tool with one parameter and moderate complexity, it's adequate but has clear gaps in usage guidance and transparency.

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 the reset parameter fully documented in the schema. The description adds no additional parameter semantics beyond what's in the schema (e.g., no extra context on reset implications). The example references reset but doesn't enhance understanding. Baseline 3 is appropriate given high schema coverage.

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 with specific verbs ('Get server performance metrics and usage statistics'), identifying the resource (server metrics/statistics). It distinguishes itself from most siblings (e.g., get_account_status, health_check) by focusing on performance data, though it doesn't explicitly differentiate from health_check, which might overlap in monitoring functions.

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 when to choose get_metrics over health_check (a sibling tool) or other monitoring-related tools, nor does it specify prerequisites or exclusions. The example shows usage but doesn't contextualize it.

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