langfuse-mcp-java

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

ANNOTATION CONTRADICTION: Description explicitly states 'Read-only' but annotations declare readOnlyHint: false and destructiveHint: true. This is a critical safety mismatch. Additionally fails to explain openWorldHint: true implications (external dependencies) or output format.

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?

Three-sentence structure is appropriately front-loaded (what, when, safety), but the 'Read-only' sentence earns no place since it contradicts annotations and misleads the agent about safety profile.

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?

Describes the return value conceptually (schema, types, enums) which compensates somewhat for missing output schema. However, the annotation contradiction creates a critical gap in behavioral understanding, and no pagination or format details are provided.

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?

Input schema has zero parameters, establishing baseline of 4. No parameters require semantic explanation beyond the schema definition.

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?

Excellent specificity: states the verb (Returns), resource (Langfuse data model schema), and detailed scope (all entity types, fields, and valid enum values). Clearly distinguishes from sibling data-fetching tools like fetch_traces or get_dataset by focusing on metadata/schema rather than instance data.

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?

Strong explicit guidance: 'Call this first before running any query to understand the available data structures' establishes prerequisite usage and explains the 'why.' Would be perfect (5) if it explicitly contrasted with specific alternatives like fetch_traces.

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