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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered. The description adds real context beyond that: results are ordered heaviest-first, and the payload includes a rule-kind catalog and weekly stopped-result counts. It stops short of explaining what 'MASTER stopped' means or the response shape.

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?

A single dense sentence with the primary payload front-loaded and the optional flag last. It earns its length, though the compressed jargon ('heaviest first', 'MASTER stopped') slightly undercuts readability.

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?

With no output schema, the description must convey the return structure; it sketches three parts (ordered live rules, rule-kind catalog, weekly stop counts) but leaves the meaning of key terms and the shape of each part ambiguous. Adequate but not sufficient for confident invocation.

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Schema coverage is 100% and the schema already explains history as 'last 50 retired rules (superseded decisions included)'. The description's 'history: true adds the last 50 retired rules' largely restates it, adding only marginal framing – baseline 3 applies.

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 names the resource ('this line's rider') and what is returned (live rules, catalog of rule kinds, weekly stop counts), so the basic read operation comes across. However, 'rider' and 'MASTER' are undefined domain jargon, and nothing distinguishes it from siblings like line_rider_put, line_rider_retire, or line_wiring_list.

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?

There is no statement of when to call this versus line_rider_put/line_rider_retire or other line_* tools. The only conditional mentioned (history:true) is a parameter option, not usage guidance.

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