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

Annotations already declare a destructive mutation with readOnlyHint=false and destructiveHint=true. The description adds useful context beyond them: it restores the prior version, affects the old part and mix, has no cost, and is limited to reversing only the latest redo. It does not cover auth requirements or error behavior, but the safety-relevant scope is clear.

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 three tight sentences with the action and scope front-loaded. The cost note and the last-redo limitation are relevant and earn their 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 destructive mutation tool with no output schema, the description explains what is reverted, what it costs, and the main limitation, while annotations cover the safety profile. Auth, permission, and error details are not covered, but the core behavioral context is adequate.

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%, and both id and version are documented in the schema. The description refers to the song's version but does not add parameter-specific meaning beyond what the schema already provides, so the baseline 3 is appropriate.

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 description states a specific verb and resource: putting a song's version back to before its last redo_stem. It also names redo_stem and clearly distinguishes undoing from redoing, so an agent can tell what this tool does without opening the schema.

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?

It gives the key precondition that only the last redo can be undone and references redo_stem as the operation being reversed. It does not explicitly route to alternatives such as using redo_stem to reapply or what to do when no redo exists, but the usage context is clear.

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