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

Annotations already declare this is a non-idempotent, non-destructive write, so the safety profile is covered. The phrase 'it waits until they come back' usefully discloses asynchronous, delayed delivery, but the description says nothing about persistence, whether the recipient can reply, or what happens on invalid names.

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?

A single compact sentence with the core action and addressing rule front-loaded and no filler. It is perhaps too terse, 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?

An output schema exists, so return values need not be explained. For a write tool with asynchronous behavior, the definition is minimally adequate but omits recipient-facing semantics and error conditions.

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 100%, so all three parameters (to, body, api_key) are already documented in the schema. The description only restates the addressing rule for 'to' and adds no syntax, format, or constraint detail beyond the schema.

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 and resource ('write to a citizen') and clarifies the addressing modes (inner name or public name). It is clear what the tool does, though it does not explicitly distinguish itself from siblings like nation_say or nation_letters.

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?

Offers no guidance on when to use this versus nation_say, nation_letters, or other messaging tools, and no exclusions or prerequisites. The async delivery note hints at behavior but not at usage conditions.

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