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 discloses that the tool outputs 'Source roots with packages and file counts' and has a prerequisite, but lacks details on performance, error handling, or data format. It adds some behavioral context but not comprehensively.

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, prerequisite) and uses minimal sentences. However, the 'OUTPUT' line could be integrated more smoothly, and some phrasing is slightly redundant, but overall it's efficient and front-loaded.

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 no annotations and no output schema, the description provides basic purpose, usage, and output details, but lacks information on return format, error cases, or performance. It's adequate for a read-only tool but has gaps in fully contextualizing the tool's behavior.

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 the two parameters. The description does not add any parameter-specific information beyond what the schema provides, such as explaining the impact of 'includeFiles' or 'maxDepth' on the output structure.

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 action ('Get project structure') and resource ('package hierarchy'), distinguishing it from siblings like 'get_classpath_info' or 'get_dependency_graph' by focusing on package tree visualization rather than dependencies or classpath details.

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?

It explicitly states when to use this tool ('Call to see the package tree') and includes a prerequisite ('Requires load_project to be called first'), providing clear guidance on usage context and dependencies without misleading information.

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