reaches

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuine behavioral context beyond that: it returns the shortest path, and it explicitly reports when no path exists within the depth limit — a notable outcome an agent must handle. It does not describe the return shape, but without an output schema that is a modest gap.

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 tight sentences, front-loaded with the core action and immediately followed by the disambiguation clause. Every clause carries information; nothing is redundant.

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 3-parameter read-only graph query with full schema coverage and no output schema, the description covers purpose, scope, failure signaling, and alternatives. The only shortfall is the absence of any hint about the result's shape (e.g., the chain as an ordered list of symbols), which an agent might want when interpreting output.

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% and all three parameters are documented in-schema, including depth default 24 and max 64. The description's phrase 'within depth' reinforces the depth parameter's role as a search bound, but adds no syntax or format detail beyond the schema. Baseline 3 is appropriate.

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 (find shortest call chain) with the exact resource endpoints (function to function or import) and its depth bound. It also names the two sibling tools it is not, so an agent can distinguish it from callgraph and xrefs purely from the text.

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?

Explicit exclusions with the alternatives named: 'Not for the whole neighbourhood (use callgraph) or direct callers (use xrefs)'. That is a textbook when-not plus alternative mapping, leaving no ambiguity about tool selection.

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