langfuse-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. It mentions that filters are optional but doesn't describe key behaviors: whether this is a read-only operation, if it has rate limits, what the output looks like (though an output schema exists), or any performance implications (e.g., pagination details beyond schema). The description is too sparse for a tool with 10 parameters and no annotation support.

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—just two sentences—and front-loaded with the core purpose. Every word earns its place, with no wasted text. It efficiently communicates the essential information without unnecessary elaboration.

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 (10 parameters, 1 required) and the presence of an output schema, the description is minimally adequate. The output schema reduces the need to explain return values, but the description lacks context on behavioral traits (e.g., read-only nature, performance) and usage guidelines. It meets a bare minimum but leaves gaps for an agent to understand when and 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 adds minimal value beyond the schema by stating 'All filter parameters are optional,' which clarifies that filters can be omitted, but this is somewhat redundant since the schema shows defaults and optionality. No additional parameter semantics are provided in the description.

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: 'Find traces based on filters.' It specifies the verb ('find') and resource ('traces'), and mentions that all filter parameters are optional, which adds useful context. However, it doesn't explicitly differentiate this tool from its sibling 'fetch_trace' (singular), which appears to fetch a single trace rather than multiple traces with filtering.

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 sibling tools like 'fetch_trace' (for single traces) or 'fetch_sessions' (which might relate to traces), nor does it specify prerequisites or exclusions. The only usage hint is that filters are optional, which is minimal guidance.

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