get_chain_controls

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

Annotations already indicate readOnlyHint=true and openWorldHint=true, and the description adds substantial behavioral detail beyond that: 5-minute cache refresh, explicit off-season no-controls response instead of empty list, the meaning of each restriction level, and the caution that requirements change hour to hour. This fully informs the agent about expected behavior and edge cases.

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 description is longer than average, but every section earns its place: source, levels, refresh, filters, off-season behavior, and safety caveat are each separated into digestible chunks. The primary purpose is front-loaded, and there is no redundant filler or repetition of the tool name.

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?

Given the absence of an output schema, the description still covers the essential invocation knowledge: data source, checkpoint routes, filter semantics, refresh cadence, off-season response, and the need to surface data_as_of time. An agent can select, call, and interpret the result correctly from this description alone.

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 carries full responsibility for explaining parameters. It does so with concrete examples: route accepts forms like '80', 'US-50', and 'SR-88'; center is a 'lat,lon' string; radius_km scopes checkpoints around a place such as Truckee. This adds meaning far beyond the bare schema property names.

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 a specific resource ('current chain-control requirements on California mountain highways') and a specific verb ('get'), then distinguishes its domain from sibling traffic tools like incidents, lane closures, wildfires, cameras, road signs, and events. It also defines the R-1/R-2/R-3 levels, making the tool's purpose concrete and actionable.

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 description gives clear when-to-use context: it names the data source, the available filter modes (route vs. center+radius), and the off-season behavior. It advises on how to handle rapidly changing conditions, but it does not explicitly say when to use this tool instead of a sibling like check_route or get_incidents, so it stops short of full exclusion guidance.

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