who_calls

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

With no annotations, the description carries the behavioral burden. It discloses that each edge reports the rule that produced it and warns that sub-0.5 edges are leads rather than facts. It does not discuss cost or traversal size, but the output schema covers result shape.

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?

Three compact sentences deliver the definition, the trigger scenario, and the confidence caveat. The description is front-loaded with the core purpose and every sentence adds distinct value.

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 analysis tool with a full output schema and fully documented parameters, the description covers what the tool computes, when to use it, and how to interpret weak results. Nothing essential is missing for selecting and invoking it correctly.

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?

All four parameters already have schema descriptions, so the baseline is 3. The description adds meaningful semantics for min_confidence, explicitly saying sub-0.5 edges should be treated as leads, and implies that depth and limit control transitive expansion.

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 states a specific action and resource: 'Reverse call tree: everything that reaches this symbol, transitively.' This clearly distinguishes it from forward-call tools like what_it_calls without needing extra inference.

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 gives concrete guidance on when to use the tool: 'The tool to use before changing a signature, tightening a validation, or deleting anything.' It does not explicitly list exclusions or alternatives, but the use-case framing is clear and actionable.

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