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

With no annotations, the description carries the full burden and does disclose key traits: cost ("Free"), a quota ("daily limit"), a single-change limit, identity preservation, and that the result is displayed. It omits what happens at the daily limit, whether the operation is reversible, and whether the draft is consumed.

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 action and constraint, then cost, then the prerequisite. Every sentence carries information the agent cannot get from the schema or annotations.

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 one-parameter mutation with no output schema, the description covers scope, identity preservation, cost, quota, and the prerequisite, and states that a picture is returned. Remaining gaps are quota behavior past the daily limit and the draft's state after the call.

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% and already supplies examples and a length range, so the schema does the heavy lifting. The description adds one genuinely useful constraint the schema lacks — that only one change may be requested at a time — but nothing else about how to phrase the change.

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 ("Change one thing about the presenter picture just made") and immediately bounds scope with "keeping the same person" plus an enumeration of changeable attributes. The closing clause routes the agent away from make_presenter/draw_presenter by tying it to an existing draft.

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?

Gives a hard precondition — "Only works on an unmade draft from draw_presenter" — which is exactly the when-to-use information an agent needs to avoid a failed call. It does not say what to do instead when the draft is already made or when multiple changes are wanted, so the sibling routing is incomplete.

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