javalens-mcp

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

With no annotations provided, the description carries the full burden and does well by disclosing key behavioral traits: it requires 'load_project to be called first' (prerequisite), uses 'ZERO-BASED coordinates' (input format), and specifies the output ('All locations where the method is used as a method reference'). It lacks details on error handling or performance limits.

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 appropriately sized and front-loaded with the core purpose. Each section (JDT-UNIQUE, USAGE, OUTPUT, Useful for, IMPORTANT, Requires) adds value without redundancy. Minor improvements could include merging some bullet points for tighter flow.

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 (fine-grained search), lack of annotations, and no output schema, the description is fairly complete. It covers purpose, usage, output, prerequisites, and technical details. It could improve by briefly mentioning the return format or error cases, but it's largely adequate.

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. The description adds no additional parameter semantics beyond what the schema provides, such as explaining coordinate systems or file path formats, meeting 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 specific verb ('Find all method reference expressions') and resource ('Foo::bar lambda syntax'), distinguishing it from siblings like 'find_references' by specifying it targets method reference expressions only. The 'JDT-UNIQUE' note further differentiates it from LSP-based tools.

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 clear context on when to use it ('Position on a method, or provide method details') and lists specific use cases ('Understanding functional programming patterns', 'Finding lambda-style usages', 'Refactoring analysis'). However, it does not explicitly state when not to use it or name alternatives among siblings.

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