redo

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

With no annotations provided, the description carries the full burden of explaining behavior. It states only what redo does (restores the last undone operation) but does not disclose failure modes (e.g., if there is nothing to redo), whether it is a mutating operation, or any side effects. This is a significant gap for a state-changing tool.

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, front-loaded sentence that conveys the essential meaning without any wasted words. It is optimally concise for the simplicity of the operation.

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?

Although the tool is simple and has no parameters, the description lacks critical context about edge cases (e.g., behavior when no undo history exists). With an output schema present, return values are presumably covered, but the description still feels incomplete for a tool that modifies state. It meets the minimum viable threshold.

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 schema fully covers parameter meanings. The description does not need to compensate for any parameter details. The baseline of 4 applies because the schema and description together are sufficient for a no-argument tool.

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 'Redo the last undone operation' clearly identifies the action (redo) and the target (the last undone operation). It is specific enough to distinguish it from the sibling 'undo' tool, though it does not explicitly reference that sibling.

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?

No guidance is given about when to use this tool versus alternatives. It implies it follows an undo, but does not state prerequisites, exclusions, or situations where redo would be inappropriate. There is no mention of the sibling 'undo' tool or the need to have an undo history.

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