Unique callees per function

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

The readOnlyHint annotation already establishes that this is a safe read operation. The description adds that results are unique and capped by limit, but does not disclose anything further about behavior such as instance targeting or output structure. With annotations covering safety, this is minimally adequate.

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?

It is a single front-loaded sentence with no filler. Every clause contributes directly to understanding what is returned and the cap behavior.

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?

Output schema exists, annotations cover read-only safety, and parameters are fully documented in the schema, so the description does not need to explain return values. However, for a tool with many graph-related siblings, it lacks routing guidance that would make selection unambiguous.

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 addrs, limit, and instance_id are fully documented in the schema. The description only restates the limit cap idea and adds no syntax or format meaning beyond what the schema already provides.

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 verb and resource: returning unique callees per function, with a limit cap. It is clear what the tool does, but it does not distinguish itself from related siblings such as callgraph or xrefs_to.

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?

There is no when-to-use guidance, no alternatives mentioned, and no conditions for choosing this tool over callgraph or other graph/query tools. Usage context is only implied by the tool name and description.

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