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

Annotations declare readOnlyHint=false with destructiveHint=false, and the description explains exactly why that combination holds: nothing is lost because the restore is applied as a new entry. It also discloses reversibility via the undo path on edit_sheet/edit_slides, which is genuine behavioral context beyond the annotations.

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?

Three short sentences, front-loaded with the core effect and followed by the safety guarantee and the undo path; nothing is padding. Minor deduction for the awkward phrasing 'A sheet or Slides is made as it was then', which is grammatically rough and slightly obscures the target types.

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 two-parameter mutation tool with no output schema, the description covers the essential questions: what changes, whether data is lost, and how to reverse it. It leaves a small gap about whether restore works only for sheets/Slides or also for docs and boards, and does not say what the call returns.

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?

Schema description coverage is 100%, so both `doc` and `entry` are already documented in the schema, including the constraint that entry is a positive integer from history. The description adds no format, range, or validation detail beyond that, so the baseline of 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 and resource: it makes an older History entry the current one, and does so by creating a new entry rather than rewriting the old one. That distinguishes it from the read-only `history` sibling and from the `edit_*` mutation tools, though it never names `history` as the source of the entry number.

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 rather than stated: an agent can infer this is the revert-to-a-previous-state tool and that `edit_sheet`/`edit_slides` with undo is the inverse operation. There is no explicit 'use this when...' clause and no pointer to `history` as the prerequisite step for obtaining a valid entry number.

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