3D-MCP

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

No annotations are provided, so the description must fully disclose behavioral traits. 'Undo the last operation' implies a mutation that reverses a previous action, but it fails to describe critical aspects: whether it's destructive (e.g., overwrites data), requires specific permissions, has side effects (e.g., affects selection state), or handles edge cases (e.g., what happens if no operation exists). The description is too minimal to inform safe or effective use.

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, clear sentence with no wasted words. It's front-loaded with the core action ('Undo'), making it immediately understandable. This efficiency earns a top score for conciseness.

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 complexity of an undo tool (a mutation with potential side effects), no annotations, and no output schema, the description is incomplete. It lacks details on behavior, return values, error conditions, and interaction with sibling tools like 'redo'. For a tool that modifies state, this minimal description is inadequate for safe agent invocation.

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, meaning no parameters are documented in the schema. The description doesn't add parameter details, which is appropriate since there are none to explain. A baseline of 4 is applied for zero parameters, as the description doesn't need to compensate for missing schema information.

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 target ('the last operation'), making the purpose understandable. However, it lacks specificity about what constitutes an 'operation' in this context (e.g., modeling actions, edits, transformations) and doesn't differentiate from its sibling 'redo', which is a closely related tool in the list. This vagueness prevents a higher score.

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., requires a prior operation to undo), exclusions (e.g., cannot undo certain irreversible actions), or comparisons to sibling tools like 'redo' for reversing the undo. This absence of usage context leaves the agent without direction.

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