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

Annotations already declare non-read-only, non-destructive, and idempotent behavior, so the description only needs to add context. 'The earlier baseline comes back' usefully reveals the restoration effect, but it does not clarify scope of reversal (single comparison vs. batch) or what happens when there is nothing to undo.

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 compact sentence with the action and scope front-loaded and no filler. The trailing clause after the colon is slightly loose but still earns its place by describing the outcome.

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 one-parameter undo tool with full schema coverage, 100% param documentation, and no output schema, the description covers action, scope, and effect adequately. Only the empty-state and sibling-routing details are 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?

Only one parameter and the schema documents it fully (comparisonId with its origin in get_run visualComparisons[]), so the schema carries the semantic load. The description adds no parameter-level meaning beyond what the schema states; 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 the exact action reversed (the last accept or ignore), plus the scope (this page, device and browser). It clearly distinguishes itself from undo_structure_review by naming the visual decision class, though it never cites that sibling by name.

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 phrase 'the last accept or ignore' implies when this applies, but there is no explicit statement of preconditions (e.g. that a decision must exist), no exclusion, and no pointer to undo_structure_review for structural decisions. Usage is inferable rather than stated.

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