Undo

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

Annotations indicate this is a non-read-only, non-idempotent, non-destructive operation, which the description aligns with by implying mutation ('undo') without destruction. However, the description adds minimal behavioral context beyond annotations—it doesn't specify what 'last operation' means (e.g., scope, limitations), whether it's reversible, or error conditions. With annotations covering safety aspects, a baseline score of 3 is appropriate as the description adds some value but lacks rich behavioral details.

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, efficient sentence ('Undo the last operation') that directly states the tool's purpose with zero waste. It's front-loaded and appropriately sized for a simple tool with no parameters, making it easy to parse quickly.

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?

Given the tool's simplicity (0 parameters, no output schema) and annotations that cover key behavioral hints, the description is minimally complete. However, it lacks context about what constitutes an 'operation' in this CAD environment, potential limitations (e.g., only undoing certain types of changes), or expected outcomes, which could help an AI agent use it more effectively. It's adequate but has clear gaps in contextual detail.

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 input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description doesn't add parameter details, which is acceptable here. A baseline score of 4 is given because the schema fully handles parameters, and the description appropriately focuses on the tool's action without redundant parameter explanations.

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 'Undo the last operation' clearly states the verb ('undo') and resource ('last operation'), making the purpose understandable. However, it doesn't distinguish this tool from potential alternatives like 'redo' or 'history' tools that might exist in other contexts, and it's somewhat vague about what qualifies as an 'operation' in this CAD environment. It avoids being a tautology of the name/title by specifying 'last operation'.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., requiring a previous operation to undo), exclusions (e.g., irreversible operations), or compare it to sibling tools like 'delete_all' or 'suppress_feature' that might handle similar undo-like actions. Usage is implied by the name but not explicitly stated.

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