call_hierarchy

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

With no annotations, the description is the only behavioral disclosure: it correctly identifies the tool as a read-only trace and explains the default-incoming branch. It leaves out notable behavior such as whether it works without a prior prepare_call_hierarchy call, whether results are scoped to the project/index, and any latency or size concerns for deep call graphs.

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?

Two short sentences, front-loaded with the core action and the direction switch, with no filler. It is efficient to the point of under-specification, but nothing written is wasted.

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?

An output schema exists so return values needn't be described, but for a 5-parameter LSP tool with zero schema coverage and no annotations the description is too thin: missing position semantics, the role of symbol_name, and the relationship to the prepare_call_hierarchy sibling are all conditions an agent needs to call this 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?

Schema description coverage is 0%, so the description must carry parameter meaning, yet it explains only 'direction' (partially – incoming/outgoing) and never defines file_path, line, character, or symbol_name. A caller cannot tell whether the position is 0- or 1-based, what units 'character' uses, or why symbol_name is optional.

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?

States a specific verb and resource ("Trace caller/callee relationships for a function or method") and disambiguates the two directions, so an agent knows it is a relationship-tracing tool. It does not distinguish itself from the similar sibling prepare_call_hierarchy or find_references, so the agent must guess at the boundary.

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 direction values give implicit guidance on which mode to pick, but there is no explicit when-to-use versus find_references/get_type_hierarchy/prepare_call_hierarchy, and no statement of prerequisites (e.g. whether a prepared hierarchy is required first). Usage is inferable but not stated.

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