find_callers

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

No annotations are provided, so the description carries the burden. It discloses performance ('Fast operation 1-2s') and the underlying mechanism ('pre-built call graph'), which adds useful context. However, it does not explicitly state that the operation is read-only or describe error handling or edge cases, leaving some transparency gaps.

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 with labels (PURPOSE, USAGE, PERFORMANCE, WORKFLOW, TIP) and front-loaded with the core action. It is slightly longer than necessary, with some repetition of the purpose in the TIP, but every section contributes meaningful context.

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 simple one-parameter tool with no output schema, the description covers purpose, usage, performance, and workflow, giving an agent enough context to decide when and how to use it. It does not explicitly describe the return format or behavior when no callers are found, but these are inferable from the stated purpose.

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 is 100% with a descriptive parameter entry ('Function name to find callers for (supports method names with class context)'). The description adds no additional parameter details beyond the schema, so the baseline 3 applies.

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 'Find all functions that call the specified function' with a specific verb and resource. It further explains it identifies the call hierarchy, which distinguishes it from sibling tools like find_callees, and is well-scoped.

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 provides clear usage context: 'Use when analyzing function dependencies, planning refactoring, or understanding code flow patterns.' It also includes a workflow showing where find_callers fits relative to find_definition and find_callees, but it does not explicitly mention alternatives or when not to use it.

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