Redo

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

Beyond the annotations, the description reveals critical behavioral details: the headless backend environment variable requirement, the shared undo history, and the redo-branch discard semantics. This gives the agent important expectations about failure modes and state changes.

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 concise and well-structured: the core purpose is front-loaded in the first sentence, followed by necessary caveats. Every sentence adds meaningful information without redundancy.

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 (no parameters) and the presence of an output schema, the description fully covers the operational context: how redo relates to undo, the environment prerequisite, and when redo becomes invalid. Nothing critical is missing.

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 parameter semantics are not a burden on the description. The baseline of 4 applies, and the description correctly focuses on behavioral context rather than parameter details.

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 opening sentence 'Reapply the operation you just undid' uses a specific verb and resource, clearly defining the tool's purpose. It also implicitly distinguishes this from drawing_undo by describing the inverse operation while referencing the same undo history.

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 explains that redo shares history with drawing_undo and requires EZDXF_UNDO_DEPTH, which tells the agent when the tool will work. It also gives an explicit limitation: drawing after an undo discards the redo branch, making it clear when redo is no longer applicable.

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