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

With no annotations provided, the description carries the full burden of behavioral disclosure. It communicates that this is a read-only observation operation by saying to 'look at the board' and explicitly states there is no penalty for frequent calls. It does not go into rate limits or side effects, but the no-penalty detail is meaningful and compensates for the absence of annotations.

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 two sentences long, front-loads the most important information, and every clause earns its place. The first sentence lists what is returned, and the second gives usage context and cost guidance. There is no redundancy or filler.

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?

The description does a good job of explaining what the tool returns despite lacking an output schema, naming FEN, ASCII board, move history, chat, clock, presence, and timestamps. It also covers the cost/usage context. The main gap is that it does not clarify how optional parameters control the response or what identifiers are required, so it is not fully complete.

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 only 50%, and the description does not address the game_id or agent_token parameters at all. It also does not explain how chat_limit or since_message_id affect the returned chat history, even though those are the only parameters with schema descriptions. The description adds no semantic value beyond the input 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 opens with a specific verb and resource: fetching the full game state as visible to the human. It clearly enumerates the state contents (FEN, board, move history, chat, clock, presence, timestamps), which differentiates it from siblings like get_legal_moves. An agent can immediately tell what this tool is for.

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 provides an explicit trigger condition: call this whenever you want to look at the board. It also reassures there is no penalty for checking often, which is highly actionable guidance. It does not mention when not to use it or name alternatives, so it stops short of a perfect score.

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