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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile is known. The description adds a semantic focus but doesn't mention performance implications, output structure, or any constraints on revisions. It adds modest context beyond 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?

The description is a single sentence, front-loaded with the core action. It is concise, but could be more structured with a brief note on usage or output.

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 read-only diff tool with full schema coverage and no output schema, the description covers the main purpose. However, it lacks detail on the response format or any edge cases (e.g., invalid revisions), which might be inferred by an agent but are not explicit.

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 coverage is 100%, so all parameters are described adequately in the schema. The description adds no extra parameter semantics, which is acceptable given full coverage.

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 clearly states it diffs two revisions semantically, listing the specific aspects (objects, transforms, materials, render settings). However, it doesn't explicitly differentiate from sibling tools like revision_restore or scene_inspect, which could overlap in purpose.

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 description implies a comparison use case but provides no explicit when-to-use or when-not-to-use guidance. With siblings like revision_restore and scene_inspect, clearer routing would be helpful.

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