nexus-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 describes the return format (a dict with specific keys and None values when unset), which is useful context. However, it doesn't mention other behavioral traits like whether it's read-only, has side effects, or any rate limits, leaving gaps in transparency.

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 front-loaded with the core purpose in the first sentence, followed by specifics about the return format. Every sentence earns its place by providing essential information without waste, making it efficient and well-structured.

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 has 0 parameters, an output schema exists, and no annotations, the description is fairly complete. It explains what the tool does and the return format, which compensates well. However, it could be more complete by addressing behavioral aspects like read-only nature or usage context relative to siblings, slightly reducing the score.

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 input schema has 0 parameters with 100% coverage, so there's no need for parameter details in the description. The description appropriately focuses on the return value instead. Since it adds value by explaining the output structure, it scores above the baseline of 3 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: 'Return the current session preferences.' It specifies the verb ('Return') and resource ('current session preferences'), making it easy to understand. However, it doesn't explicitly differentiate from siblings like 'clear_preferences' or 'set_preferences' beyond implying it's a read operation, which is why it's not a 5.

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 implies usage by stating it returns preferences, suggesting it should be used when you need to check current settings. However, it doesn't provide explicit guidance on when to use this vs. alternatives like 'set_preferences' or 'clear_preferences', nor does it mention any prerequisites or exclusions, leaving some ambiguity.

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