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

Annotations already cover readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is disclosed. The description adds valuable behavioral context by stating it walks exactly one hop and returns both outgoing and incoming relations. Edge cases like unknown ids or empty results are not mentioned, but the presence of an output schema mitigates that.

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 sentences with zero waste: the first states the core behavior, the second gives usage context and a route to an alternative. The most important information is front-loaded.

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 one-parameter, read-only graph traversal tool with an output schema and safety annotations, the description covers the purpose, the one-hop scope, the typical call sequence (after get_entity), and the alternative when no starting object exists. Nothing essential is missing for an agent to select and invoke it 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 100% for the single 'id' parameter, giving the agent the necessary definition. The description adds extra semantic value by framing the id as one you already have from get_entity, implying it must be a known graph object and not a search string.

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 opening phrase 'Graph neighbours of an object' names a specific verb and resource, and specifies the scope as outgoing and incoming relations with their relation types. It also distinguishes from siblings by explicitly contrasting with get_entity ('after get_entity') and search ('use search when you have a question and no starting object').

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 gives explicit when-to-use guidance: use after get_entity to widen an answer with adjacent objects, and use search instead when there is no starting object. This is a clear selection criterion among sibling tools.

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