Undo

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

Annotations already declare it is a non-destructive mutation (readOnlyHint=false, destructiveHint=false, openWorldHint=false). The description adds genuinely useful context that the undone change may belong to the user rather than the agent, but says nothing about reversibility, undo depth, or what happens if the stack is empty.

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?

A single short sentence with the operation front-loaded and no filler; the parenthetical clarification about ownership earns its place.

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?

For a zero-required-parameter mutation with annotations covering the safety profile and no output schema, the description is nearly sufficient. Only the no-op/empty-stack case is left unstated.

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?

There is only one optional parameter and the schema documents it at 100% coverage ('Target tab id. Defaults to the active tab.'). The description adds no extra meaning beyond the schema, so the baseline 3 applies.

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 verb (undo) and target scope (the last change on the tab), which unambiguously separates it from siblings like snipaya_redo or snipaya_delete_items. It does not explicitly name the sibling it pairs with, but the operation is self-evident.

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?

Usage is implied by 'undo the last change' but there is no explicit when-to-use/when-not guidance, no mention of snipaya_redo as the inverse, and no stated behavior when there is nothing to undo. Adequate but leaves the agent to infer.

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