undo_move_tool

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

With no annotations, the description carries the full burden of behavioral disclosure. It accurately states the return behavior (new board state in FEN format or an error if no moves to undo) and that both player and AI moves are reversible. It does not mention deeper side effects, such as whether undo is limited to the current session or whether it resets AI internal state, but the core behavior is disclosed.

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 extremely concise: three short sentences that front-load the purpose, add scope, and then specify arguments and return format. There is no redundant information 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?

For a zero-parameter tool with an output schema indicating FEN return, the description is sufficient. It covers the operation scope (player and AI moves) and the error case. It could be slightly more explicit about the irreversible nature of the undo or what happens in an initial board position, but the error message is implied. Overall, it is well-composed for the tool's simplicity.

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?

The tool has zero parameters, so the baseline is 4. The description explicitly lists 'Args: None,' which adds clarity beyond the empty input schema and confirms no arguments are needed.

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 clearly states the tool's function: 'Undoes the last move made on the board.' It also specifies it can undo both player and AI moves, distinguishing this from related tools like make_move_tool and ai_make_move_tool. The verb-resource pairing is specific and unambiguous.

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 implies usage (when you want to revert a move) but does not explicitly state when to use this tool over alternatives or provide exclusion criteria. No comparison to sibling tools is given, leaving the agent to infer from the tool name and description.

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