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 key behavioral traits: it returns specific output details (method signature, parameters, etc.), uses zero-based coordinates (important for correct usage), and has a prerequisite ('load_project'). However, it doesn't mention error handling, performance implications, or whether it's read-only (though 'Get' implies safe read).

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 front-loaded: the first sentence states the purpose, followed by usage, output, important note, and prerequisite. Each sentence earns its place with no wasted words, and the bullet-like formatting enhances readability without verbosity.

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 complexity (positional analysis in code), no annotations, and no output schema, the description is reasonably complete. It covers purpose, usage, output details, coordinate system, and prerequisites. However, it lacks information on error cases (e.g., invalid positions) and doesn't fully describe the output structure, which could be helpful since there's no output schema.

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, clearly documenting all three parameters. The description adds value by emphasizing 'ZERO-BASED coordinates,' which clarifies the semantics of 'line' and 'column' beyond the schema's generic descriptions. It doesn't provide additional syntax or format details, but the schema already does the heavy lifting, warranting a baseline score of 3.

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 method information at a specific position.' It specifies the verb ('Get') and resource ('method information'), and distinguishes it from siblings like 'get_field_at_position' or 'get_type_at_position' by focusing on methods. However, it doesn't explicitly differentiate from 'analyze_method' or 'get_signature_help' in terms of scope or granularity.

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 guidance: 'USAGE: Position on a method reference or declaration' clarifies when to use it, and 'Requires load_project to be called first' states a prerequisite. While it doesn't name specific alternatives, the context of sibling tools (e.g., 'analyze_method' for broader analysis) implies differentiation, and the positional focus is clear.

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