javalens-mcp

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

With no annotations provided, the description carries full burden and does well by disclosing key behavioral traits: it specifies the coordinate system ('Uses ZERO-BASED coordinates'), describes the output format ('Comprehensive info including kind, modifiers, signature, location'), and states a prerequisite dependency ('Requires load_project to be called first'). However, it doesn't mention performance characteristics, error conditions, or limitations.

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 efficiently structured with clear sections (purpose, usage, output, important note, prerequisite), uses bullet-like formatting without actual bullets, and every sentence earns its place by providing essential information without redundancy.

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?

For a read-only information retrieval tool with no output schema, the description provides good coverage: clear purpose, usage context, output format description, coordinate system specification, and prerequisite. It could be more complete by describing potential error cases or limitations, but covers the essential context well given the tool's complexity.

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. The description adds marginal value by reinforcing the zero-based nature of coordinates, but doesn't provide additional semantic context beyond what's in the schema descriptions. This meets the baseline expectation when schema coverage is complete.

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 with specific verb ('Get detailed information') and resource ('about any symbol at a position'), and distinguishes it from siblings by specifying it works on 'any symbol (type, method, field, variable)' rather than focusing on specific analysis types like the many 'analyze_' or 'find_' 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 for when to use the tool ('Position on any symbol') and includes an important prerequisite ('Requires load_project to be called first'), but doesn't explicitly state when NOT to use it or name specific alternatives among the many sibling tools.

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