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

Annotations declare destructiveHint=true and idempotentHint=false, so the agent knows this mutates state and is not idempotent. The description adds genuinely useful behavior that annotations cannot convey: the replaced version is retained, so calling it again acts as a redo, and two undos cancel out. It could go further on permissions or what happens when there is no prior change, but it is strong for this tool.

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 compact sentences: the core action comes first, then the undo/redo semantics, then the alternative for deeper history. Every sentence earns its place with no filler.

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 single-parameter mutation tool with annotations covering safety and no output schema, the description gives the key state semantics and routing to list_versions/restore_version. It does not cover behavior when there is no prior change to undo, which is a minor gap rather than a blocker.

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 the single 'name' parameter is already documented as the film's prj_… id on the user's account. The description adds no parameter detail 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+resource ('Put a film back as it was before its last change') and defines what counts as a change by naming edit_film, set_brand, and restore. It is immediately distinguishable from restore_version and list_versions, which are named as alternatives for deeper history.

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?

Explicitly says when to use it (to undo the most recent change) and when to use a different tool (use list_versions and restore_version to go further back). It also warns that two undos cancel out, which is essential usage guidance for an agent deciding whether to call it repeatedly.

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