function.callers

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

With no annotations provided, the description carries full burden for behavioral disclosure. The single sentence 'Callers of a function.' reveals nothing about side effects, mutability, required permissions, or what happens if the function_start is invalid. It does not state whether the tool reads or writes, nor any performance implications.

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 extremely short (3 words), but under-specification is not conciseness. It lacks structure and key information about inputs, output, and context. It could be expanded to several sentences without becoming verbose.

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 of a function callers tool (likely returning many results per function, requiring analysis state, etc.), the description is severely incomplete. There is no output schema, no mention of return format, and no details on edge cases (e.g., function with no callers, indirect calls, thunks). The tool cannot be used correctly without a much richer description.

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 0%, so the description must clarify parameter semantics. It mentions none of the two parameters (session_id, function_start). The description does not explain what 'function_start' represents (address, offset, symbolic name, index) or how the oneOf type (integer/string) is interpreted. However, the parameter names are somewhat self-explanatory, raising the baseline slightly.

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 is a vague fragment ('Callers of a function.') that does not specify a verb or resource clearly. It does not differentiate from sibling tools like 'function.callees' which also relates to functions, and the tool name 'function.callers' is only slightly more specific. Without stating what it returns (e.g., list of callers, call count, or locations), the purpose remains unclear to an AI agent.

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 no guidance on when to use this tool versus alternatives such as 'function.callees' or 'xref.code_refs_to'. There is no mention of prerequisites, limitations (e.g., requires analysis to be complete), or exclusions. An AI agent has no way to determine appropriate context for invocation.

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