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

Annotations only say it is not read-only, not destructive and not open-world; the description adds the materially important behavior that the first call returns a question instead of acting, and that the agent must relay it and re-invoke. It also discloses the downstream side effect (movement generation) and a hard policy constraint ('Never decide for the user'), which the annotations do not convey.

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?

Front-loaded with the action and its prerequisite, and the critical confirmation rule is stated plainly. There is some redundancy between 'ask it and call again with user_confirmed: true only after an explicit yes' and 'Never decide for the user', which restates the same constraint.

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 three-parameter mutation with no output schema, the definition covers the prerequisite, the confirmation protocol and the downstream effect, which is what an agent needs to drive it correctly. It does not describe what a successful call returns or what errors a wrong-state call produces, leaving some ambiguity about post-call verification.

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 the baseline is 3, but the description adds flow semantics the schema cannot: why user_confirmed exists (the two-call confirmation protocol) and what happens when it is absent. It adds little about jobId or language beyond what their schema descriptions already state.

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 names a specific verb and resource ('Approves the reference image'), states the prerequisite (the user saw it via creation_status and liked it) and the consequence ('Ania then generates the movements'). That separates it well from the state-checking siblings, though it never explicitly distinguishes it from approve_movement, which presumably approves the next artifact.

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?

Clear use condition: only after the user has seen the image and approved it, with an explicit branching rule for the confirmation form and a rule for retrying with user_confirmed: true. It does not name the alternative tool to use if the user did NOT like the image (adjust_image / redo_movement), so the negative branch is implied rather than spelled out.

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