can_undo

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

Annotations declare readOnlyHint=true and destructiveHint=false, and the description is consistent with that ('cheap yes/no', read the label before undoing). It adds useful context—that it's a cheap probe and implies no mutation—but does not contradict or substantially enrich beyond that.

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?

Two tight sentences plus a structured Returns block; front-loaded with the core purpose. Slightly verbose in the Returns section but every sentence earns its place for a zero-param tool.

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?

No output schema exists, so the description must document the return values—and it does, precisely. Missing are edge case notes beyond the reason field, but for a cheap read-only probe this is largely 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?

Zero parameters, so the schema contributes nothing; baseline is 4. The description explains the return shape ({can_undo, label, reason?}), which is the only semantic content to convey and is done thoroughly.

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?

States a specific operation ('cheap yes/no on whether anything is undoable') plus a distinctive extra output ('plus the LABEL of the entry undo would revert'). This clearly distinguishes it from siblings like get_undo_state and undo.

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?

Explicit guidance: read the label before undoing to avoid rolling back someone else's edit, and prefer get_undo_state when counts and the redo side are also wanted in the same call. This gives both when-to-use and the alternative to use instead.

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