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

With no annotations, the description carries the full burden and does disclose meaningful behavior: the returned edge's `id` is the found node's id, `score` is null until update_edge is used, and the call returns null when exhausted. It does not cover permissions, error cases, or side effects on the graph beyond the new edge, but the lifecycle contract is unusually well spelled out.

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?

One dense sentence plus one short one, front-loaded with the endpoint and no filler. The colon/semicolon chaining is information-rich rather than padded, though it reads as a run-on and could be split for scanability.

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-value documentation is not strictly required, yet the description still explains the returned fields' meaning and the exhaustion case. For a 2-parameter tool with an odd search-side effect this is nearly sufficient; only idempotency/duplicate-edge behavior is unaddressed.

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 compensate, and it does: `nid` is identified as the query node and `prefix` as the key filter with its default-when-empty behavior ('"" for any'). Both parameters gain semantics the schema lacks.

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 gives a specific verb+resource (a new edge is created) and explains the unusual search semantics: it picks the best not-yet-shown node reachable from `nid` whose key starts with `prefix`. It even names update_edge as the follow-up. It stops short of contrasting with put_edge, so an agent must infer why two edge-creation tools exist.

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?

It explicitly tells the agent to iterate ('Call again for the next') and states the terminal condition ('Null when nothing is left'), plus routes scoring to update_edge. There is no guidance on when to prefer this over put_edge/create_node, so it is clear context without full alternative disambiguation.

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