unit_home_options

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

With no annotations, the description carries the full burden and does well: it discloses the city-standing precondition, the failure behavior ('there is no button, and the answer says so'), and that the reply contains an engine-computed `cities` candidate list plus a `mission` value to feed back into unit_mission. It does not discuss any cost, cooldown, or whether re-homing is reversible.

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 key mechanic (candidate re-home cities) is front-loaded, followed by the precondition and the apply-with-unit_mission instruction. The caravan/6-gold-to-12-gold aside is motivational detail that earns some of its space by explaining why an agent would call this, but it is the most expendable sentence.

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 query tool with no output schema and no annotations, the description covers the precondition, the failure case, the shape of the reply (`cities`, `mission`), and how to act on it. Only a fuller account of the returned list's contents or the absence of side effects would push it higher.

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%, but there is only one trivial integer parameter (unit_id). The description supplies its meaning implicitly — 'the unit to be standing in one of my cities' — which is sufficient for a single obvious identifier, though it never names unit_id directly.

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 verb and resource — where a trade unit or Great Admiral 'could re-home' — and identifies the exact in-game UI it mirrors (the Change Home City / Change Port chooser). An agent can distinguish it from sibling query tools like available_unit_actions or available_trade_routes 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?

It states the precondition clearly (the unit must be standing in one of my cities) and what happens outside that condition (no button, the answer says so). It also routes the follow-up action to unit_mission with the returned mission. It stops short of naming an explicit alternative tool for the same decision, which keeps it from a 5.

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