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. It effectively discloses key behavioral traits: it's a read-only analysis tool (implied by 'Find'), outputs grouped results, and has a prerequisite (load_project). However, it doesn't mention performance aspects like execution time or resource usage, which could be relevant for a code analysis tool.

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 well-structured with clear sections (purpose, usage, output, detection list, context, prerequisites). It's appropriately sized at 7 sentences, with each sentence adding value. Minor improvement could be made by front-loading the prerequisite information more prominently.

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 moderate complexity (analysis of reflection usage), no annotations, and no output schema, the description does a good job explaining what the tool does, what it detects, why it's useful, and prerequisites. It could be more complete by describing the output format in more detail (what 'grouped by method type' means) or mentioning any limitations.

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 100% description coverage, with the single parameter 'maxResults' clearly documented in the schema. The description doesn't add any parameter information beyond what's in the schema, but since schema coverage is high, the baseline score of 3 is appropriate as the schema adequately handles parameter documentation.

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 as finding Java reflection API usage, specifying the exact methods it detects (Class.forName, Method.invoke, etc.). It distinguishes itself from static reference searches by noting reflection calls are invisible to those, making it distinct from sibling tools like find_references or find_method_references.

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 explicitly states when to use this tool ('These usages are invisible to static reference searches and can break when types or methods are renamed') and provides prerequisites ('Requires load_project to be called first'). It also implies when not to use it by contrasting with static searches, though it doesn't name specific alternatives among siblings.

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