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 of behavioral disclosure. It effectively describes key behaviors: it's a read operation (implied by 'Get'), requires a prior action ('Requires load_project to be called first'), uses zero-based coordinates (important for correct usage), and outputs specific information (signature, Javadoc, quick info). It doesn't mention error handling, rate limits, or performance characteristics, but covers essential operational constraints.

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 and concise with four distinct sections: purpose statement, usage instruction, output specification, and important behavioral note. Each sentence earns its place by providing critical information without redundancy. The information is front-loaded with the core purpose first.

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 (position-based lookup with prerequisites), no annotations, and no output schema, the description does well by covering purpose, usage, output format, coordinate system, and prerequisites. It could be more complete by describing error cases or the exact structure of the returned hover information, but it provides sufficient context for effective use.

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 three parameters (filePath, line, column) with clear descriptions. The description adds value by emphasizing 'Uses ZERO-BASED coordinates' for line and column, which clarifies the coordinate system beyond the schema's basic descriptions. However, it doesn't provide additional syntax, format details, or examples beyond this.

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: 'Get hover information (documentation) for a symbol at a position.' It specifies the exact action (get), resource (hover information/documentation), and target (symbol at position). It effectively distinguishes itself from sibling tools like get_javadoc, get_signature_help, or get_symbol_info by focusing on IDE-like hover functionality combining signature, Javadoc, and quick info.

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 explicit usage guidelines: 'USAGE: Position on any symbol' indicates when to use it, and 'Requires load_project to be called first' specifies a critical prerequisite. It implicitly distinguishes from alternatives by not mentioning other hover-related tools, but the clear context and prerequisite make usage unambiguous.

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