available_trade_routes

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

With no annotations, the description carries the full burden and does unusually well: it discloses that yields are PER TURN, decodes the *_them field pairs, explains the food/production destination quirk, describes the list-vs-object return shape and why (no destinations => object with a reason), and specifies kind/detail behavior. It omits read-only confirmation and any error/permission caveats, so not quite a 5.

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?

Dense but front-loaded: the purpose and the establish_trade_route link come first, then field semantics, then the empty-result case. Nearly every clause carries information, though the run-on phrasing and field-pair explanations push it toward the verbose side.

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 complex query tool with no output schema, the description explains the return values thoroughly enough to interpret them. Remaining gaps (unit_id meaning, pagination/limits, what detail='summary' vs other strings do) are minor given the depth already provided.

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 compensate. It does explain the detail parameter ('full' adds `details`, the itemised gold/science hover) well, but unit_id is only implied, and the kind enum values shown are part of the output, not input parameters. Partial compensation for the coverage gap.

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 resource (valid trade-route destinations) scoped to a specific unit (caravan/cargo ship) at a specific time ('right now'), and names the sibling it feeds into (establish_trade_route). An agent can distinguish it from trade_routes and establish_trade_route without opening a 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?

Effectively tells the agent this is the prerequisite lookup before establish_trade_route by saying the trade_type is what to 'pass into establish_trade_route.' It also covers the empty-result case and the 'route starts inside one of my own cities' subtlety. Lacks an explicit when-not-to-use or a direct comparison to sibling trade_routes.

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