Databento MCP

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

No annotations are provided, so the description carries full burden for behavioral disclosure. It mentions 'resolve' but doesn't clarify if this is a read-only lookup, a transformation with side effects, or requires specific permissions. It lacks details on rate limits, error handling, or what 'resolution' entails operationally. For a tool with 6 parameters and no annotation coverage, this is insufficient.

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 states the core purpose without fluff. It's appropriately sized for the tool's complexity and front-loaded with the essential action. Every word earns its place, making it easy for an agent 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?

Given the tool's complexity (6 parameters, no annotations, no output schema), the description is incomplete. It doesn't explain what 'resolution' means in practice, what the output looks like, or any behavioral constraints. For a symbol transformation tool with multiple inputs, this leaves significant gaps for an agent to understand how to use it effectively.

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%, so the schema already documents all parameters thoroughly. The description doesn't add any meaning beyond what's in the schema—it doesn't explain parameter interactions, provide examples of symbol resolution, or clarify the relationship between 'stype_in' and 'stype_out'. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb ('resolve') and resource ('symbols'), specifying it's about converting between different symbology types. It distinguishes from siblings like 'get_symbol_metadata' or 'search_instruments' by focusing on transformation rather than retrieval or search. However, it doesn't explicitly differentiate from all siblings, leaving some ambiguity about when to use this versus similar tools.

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, context for resolution, or compare it to siblings like 'get_symbol_metadata' or 'search_instruments'. There's no explicit 'when' or 'when not' usage advice, leaving the agent to infer based on the name alone.

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