Marlo MCP

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. 'get credit score' implies a read operation but doesn't disclose any behavioral traits such as authentication requirements, rate limits, data freshness, error conditions, or what the return format might be. This leaves the agent with significant uncertainty about how the tool behaves.

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 extremely concise ('get credit score'), which could be efficient if it were informative. However, it's under-specified rather than appropriately concise—it lacks necessary details that would help the agent. While it's front-loaded (the entire description is the purpose), it fails to earn its place by being too vague.

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 complexity of a credit score tool (likely involving sensitive financial data) and the absence of annotations and output schema, the description is incomplete. It doesn't explain what the tool returns, any prerequisites, or how it fits into the broader context of sibling tools. This leaves the agent poorly equipped to use the tool 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?

The tool has 0 parameters with 100% schema description coverage, so the schema fully documents the lack of inputs. The description doesn't need to add parameter semantics, and it doesn't contradict the schema. A baseline of 4 is appropriate since there are no parameters to explain, and the description doesn't introduce confusion about inputs.

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 'get credit score' is a tautology that merely restates the tool name without adding any meaningful context. It doesn't specify whose credit score (individual, company, borrower), from what system, or with what scope. While it does contain the verb 'get' and resource 'credit score,' it lacks the specificity needed to distinguish it from potential alternatives or understand its exact function.

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. Given the sibling tools include various financial and borrower-related tools (like 'get_borrower_financial_details_for_lender'), there's no indication of whether this tool is for a specific entity type, context, or purpose. The agent receives no help in selecting this tool appropriately.

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