Undo

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

Annotations already indicate destructiveHint=true, so the description's mention of 'undo' aligns with expectations. The phrase 'whoever made it' adds context about the operation's scope, but does not disclose potential side effects (e.g., irreversibility of undone action). With annotations covering the destructive nature, this is adequate.

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, tightly written sentence that conveys the essential information without fluff. The key constraint ('whoever made it') is placed in the same sentence, making it efficient and front-loaded.

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 simple operation with zero parameters and an output schema, the description adequately explains the action. It could mention edge cases (e.g., no change to undo), but given the tool's simplicity and existing structure, it is reasonably 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?

The tool has zero parameters, so the description carries no parameter burden. The baseline of 4 for no-parameter tools is appropriate; the description adds no parameter information but none is 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 states a specific verb and resource ('Undo the last change') and clarifies the scope ('whoever made it'), distinguishing it from the sibling 'redo' tool. It is unambiguous about what the tool does.

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 when to use it (to reverse the last change) but does not explicitly state alternatives or when not to use it. It adds a usage nuance ('whoever made it') but lacks explicit routing to redo or other tools.

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