establish_trade_route

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

With no annotations, the description carries the full behavioral burden. It discloses the required unit type (caravan/cargo ship), but says nothing about what happens on failure, whether the unit is consumed or relocated, gold/maintenance costs, or the resulting state of the route. For a mutating action this is a significant gap.

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 front-loaded sentences with no filler; the primary action comes first and the parameter modes follow. The second sentence is dense but every clause carries information.

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 6-parameter tool with no annotations and no output schema, the description covers the parameter modes well but omits unit preconditions and the outcome of the action. It is minimally adequate but leaves real gaps an agent would want filled.

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 0%, so the description must compensate, and it largely does: it explains that dest_x/dest_y/trade_type come from available_trade_routes(unit_id) and that the alternative mode uses city_name with kind = international/food/production. Only unit_id is left implicit, and the mutually exclusive modes are made clear.

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 a specific verb ('Send a caravan/cargo ship') and resource ('establish a trade route'), making the action unambiguous. It implicitly distinguishes itself from siblings like plunder_trade_route and available_trade_routes by being the action that consumes the coordinates those tools produce.

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 clearly explains the two calling modes and names available_trade_routes(unit_id) as the source for dest_x/dest_y/trade_type, which is strong conditional guidance. It does not, however, state when to prefer this tool over adjacent ones (e.g. plunder_trade_route) or any preconditions such as the unit being idle.

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