Shepherd 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 mentions filtering and pagination indirectly via parameters, but lacks details on rate limits, authentication needs, error handling, or response format. This is insufficient for a list operation with 8 parameters.

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 brief and front-loaded, with two sentences that efficiently state the purpose and context. However, it could be more structured by explicitly mentioning pagination or filtering scope.

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 8 parameters, no annotations, and no output schema, the description is incomplete. It doesn't explain the return format, pagination behavior, or error cases, leaving gaps for the agent to infer usage.

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 fully documents all 8 parameters. The description adds minimal value by mentioning 'filters' but doesn't explain parameter interactions or provide examples. This meets the baseline for 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: 'List observations (generations, spans, events) with filters.' It specifies the verb ('List') and resource ('observations'), and distinguishes them as 'building blocks of traces.' However, it doesn't explicitly differentiate from sibling tools like 'langfuse_list_sessions' or 'langfuse_list_traces,' which prevents a perfect score.

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 mentions filters but doesn't specify scenarios or prerequisites, nor does it reference sibling tools for comparison. This leaves the agent without context for tool selection.

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