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

Annotations declare readOnlyHint=false and destructiveHint=false, so the write/safe profile is largely covered. The description adds real context beyond that: 'Re-renders previews' discloses a side effect and 'Free' discloses cost/credit behavior. It still omits prerequisites such as locking/unlocking state before editing.

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?

Two dense sentences with the scope front-loaded, then side effect and cost trailing. Little waste, though cramming a long enumeration into one sentence slightly hurts scannability.

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 14-parameter mutation tool with no output schema, the description covers the field groupings, the re-render side effect, and cost, which is adequate. But it omits prerequisites (existing/unlocked set, set_id provenance) and any indication of what a successful edit returns, leaving gaps an agent would want.

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?

With 14 params and only 50% schema coverage, the description meaningfully compensates by mapping parameters to concepts: headline/subline/screenshot/layout/position (move_to)/remove for a slide, opener for the opening shot, device for size, and header_* for the App Store header. The include param and set_id are left to the schema.

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 (Change/edit) and resource (a set), and enumerates the concrete facets it mutates: a slide's headline, subline, screenshot, layout, position, removal, the opener, device size, and the App Store header. This makes the tool distinguishable from design_set/create-style siblings, though it never explicitly contrasts with them.

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?

No when-to-use or when-not guidance is given. It doesn't state that the set must already exist (from design_set), whether it must be unlocked, or how this differs from design_set, add_app, or upload_screenshots. Usage is only inferable from the name.

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