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

Annotations already declare the safe read-only/idempotent/non-destructive profile, so the bar is lower, but the description adds real behavior: multiple upstream bulletin networks, that expired products are never surfaced as current, and that it is not a substitute for official advice. It stops short of stating freshness/polling or fallback behavior when no bulletin exists for a resort.

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?

Two sentences that are front-loaded with scope and source coverage, followed by a short disclaimer; little wasted text. The opening sentence is dense but readable, and the safety caveat is placed where it will be seen.

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 single-parameter read-only summary with no output schema and annotations covering the safety profile, the description does enough: it states sources, the fields surfaced, and the expiry guarantee. A note about behavior when no bulletin exists would close the remaining gap.

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?

One parameter with 0% schema description coverage, so the description carries the burden for 'resort'. The phrase 'covering a resort' anchors the parameter's meaning as a resort identifier, but supplies no format, matching, or disambiguation guidance for an undocumented free-text field.

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?

Specific verb ('Summarise') plus resource ('the regional avalanche bulletin covering a resort'), with named source networks (EAWS, avalanche.org, Avalanche Canada) and the fields returned (zone, issuing centre, issue/expiry, official link). This is clearly distinguishable from data siblings such as get_conditions, get_snow_reports or get_forecast without opening the 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?

The regional coverage statement (Europe/US/Canada) implies when the tool applies, and the closing caveat frames it as advisory rather than authoritative. However, no sibling alternative is named and no explicit when-not-to-use condition is given, so usage is only implied rather than directed.

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