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

Annotations already carry readOnly, idempotent, openWorld, and non-destructive, so safety is covered. The description adds that it returns a cue sheet and that modelVersion/units should only be set when present in the schema, which is modestly useful. It still doesn't explain what checkpoints or HOS inputs actually do to the result beyond the output schema.

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?

The opening scope and return sentence are front-loaded and useful. Later sentences drift into wrapper mechanics ('Put tool fields inside inputs', 'Do not pass the REST calculator field inside MCP arguments') that read as implementation leakage rather than tool guidance. Some redundancy ('Follow its required fields and exact choices').

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?

This is a deeply nested schema (axles geometry, HOS hour segments, checkpoints, cost inputs) and the description leaves most of it unexplained; it only covers diesel pricing, units, and modelVersion. An output schema exists so return values needn't be detailed, but the input richness far exceeds what the description addresses.

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 effectively 0%, so the description must carry the load, yet it only clarifies the dieselPrice/dieselRegion choice and modelVersion. The many nested inputs (axles, hours segments, checkpoints, heightIn, marginIn, tolls, mpg) get no explanation. Mechanical notes about the 'inputs' wrapper are not parameter semantics.

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 specific verbs and resources: screening mile-marker checkpoints, bridge inventory, federal weight and duty assumptions, and costs, plus a returns note (cue sheet). Clear what it does, but it overlaps conceptually with siblings like buscalc_map_bridge_screen and buscalc_map_marker_lookup without saying how it differs.

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 a partial rule ('Supply a diesel price or select an EIA region') for that parameter pair, but no when-to-use vs alternatives and no when-not guidance. A reader can infer it is a planning calculator, but nothing routes them here instead of the bridge or marker sibling tools.

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