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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive). The description adds behavior beyond that: season-gating, terrain-level exclusion rules, and the explicit limitation that output is not live piste status — genuinely useful context. It still doesn't disclose output shape or any latency/data-freshness traits.

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 core action is front-loaded in the first sentence, followed by scope constraints, level semantics, and a disclaimer. Every sentence carries information with no filler, though the density makes it slightly heavy for a three-parameter tool.

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 and 0% schema description coverage, the description should ideally explain the returned plan and the date/resort inputs. It covers level semantics and season gating but leaves the output format and two parameters unaddressed, so it is only adequately complete.

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 0%, so the description must carry parameter meaning. It does explain the level semantics well (easy/intermediate/advanced exclude expert, freeride and extreme terrain; only expert permits it), which maps directly to the enum. But date and resort receive no explanation beyond the season constraint, leaving part of the burden unmet.

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 and resource — 'Build modelled suggested runs in time order from forecast weather, sun, snow and mapped terrain' — so an agent knows it produces an ordered day plan. It also distinguishes itself from route_on_mountain by stating suggestions 'are not a connected route.' It stops short of clarifying its relationship to other planning siblings like best_time_to_go.

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 states important constraints (only days inside the reported winter season, summer lift/bike-park does not count) which implies when the tool is valid. However it never explicitly tells the agent when to choose this over siblings such as suggest_resort, best_time_to_go or route_on_mountain — the routing is only implicit via the 'not a connected route' caveat.

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