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

With no annotations, the description carries the full burden. It discloses that this sends exactly one private message through the in-game Phone and requires user confirmation, which adds useful context. It does not cover permissions, recipient validity requirements, rate limits, or what happens on failure.

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 a single well-formed sentence with the key action and confirmation prerequisite front-loaded. There is no wasted wording.

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?

This is a simple three-parameter action with fully described schema fields and no output schema. The description covers the action and confirmation requirement, but with no annotations and no return-value details, it leaves behavioral gaps for a mutating messaging tool.

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 are already documented in the input schema. The description adds only high-level context around confirming the message text, which maps loosely to dm_body, but adds no syntax or constraints 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?

The description states a specific verb and resource: send one private text to another player through the in-game Phone. This clearly distinguishes it from read-oriented siblings such as list_dm_threads and get_chat_with_player, though it does not explicitly name those alternatives.

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 parenthetical instruction to confirm message text with the user first is useful operational guidance. However, it does not say when to use this tool versus alternatives like search_players for finding a recipient or list_dm_threads for reading conversations.

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