explain_symbol

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 explicitly lists the output components (resolved type, signature, documentation, declaration line) and implies a read-only, non-mutating lookup by saying 'without opening the file.' It does not mention prerequisites like project indexing or error behavior, but for a simple explanation tool, the core behavior is transparent.

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 two concise sentences with no filler. The first sentence front-loads the output contents, and the second gives the practical use case. Both sentences earn their place.

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 single-parameter, read-only tool with no output schema, the description covers what the tool returns, why an agent would use it, and the expected input via schema. It could further specify naming conventions or failure behavior, but the information provided is sufficient for correct selection and invocation in most cases.

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 coverage for the single parameter is 100%, with the schema describing 'name' as 'Symbol name'. The description adds overall context about what the tool does with the symbol but does not provide additional detail about name format, qualification, or matching rules. Baseline 3 applies since the schema already documents the parameter sufficiently.

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 what the tool does: it explains what a symbol is by returning resolved type, signature, documentation, and declaration line. It also frames the specific use case ('what does this call do') and differentiates itself from siblings like find_symbol and get_symbol_body by emphasizing semantic explanation over locating or retrieving source code.

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 guidance on when to use the tool: when you need to understand what a call or symbol does without opening the file. However, it does not explicitly name alternative tools or state when not to use it, so it falls short of full exclusion-based guidance.

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