trace_path

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely non-obvious behavioral guidance — 'Read `found` and `gap` before concluding A never reaches B' — warning that a negative path result may be an artifact. It stops short of describing truncation semantics beyond naming `elisions`, but adds real value over the annotations.

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?

Five short sentences, front-loaded with the purpose, then the trigger, the argument forms, the output caveat, and the routing alternative. Nothing is padded and the reader gets the essentials first.

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 complex 8-parameter graph traversal with no output schema, the description covers purpose, triggers, alternatives, and how to interpret the key response fields (`found`, `gap`). It names truncation signals (`elisions`) but does not itself explain the response shape, leaving a small gap for a tool with no output schema.

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 the schema already documents all eight parameters including the enum direction, file-pinning, depth and char limits. The description's restatement that `from`/`to` take 'a name, an id, or name@file' mirrors the schema rather than extending it, so this lands at the high-coverage baseline.

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: 'Find how one entity reaches another, as ordered hops.' It also discriminates from the nearest sibling by naming trace_data_flow for the single-endpoint case, so an agent can choose between them without opening either schema.

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?

Gives an explicit trigger ('when your question names TWO things') and an explicit exclusion with the alternative to use instead ('One endpoint? Use trace_data_flow'). The when/when-not/alternative triad is fully present.

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