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

With no annotations, the description carries the full burden. It discloses two useful traits the schema cannot: mutations are partial ("Only what you pass changes") and the call is free. It says nothing about permissions/ownership of the agent, reversibility of the change, or the fact that nested "modern" options only take effect under design=modern, which is a real behavioral caveat.

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?

A dense telegraphic list where each clause maps to an actual parameter, so nothing is padding. The two short sentences at the end ("Only what you pass changes. Free.") are placed last, whereas the partial-update rule would be more useful front-loaded.

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 16-parameter mutation with a nested object, no annotations, and no output schema, the description gives broad field coverage but omits the relationship between design and modern, the colour field taxonomy, and any confirmation of what is returned. Adequate to start a call, not complete enough to call confidently without reading the schema.

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?

At 25% schema coverage for 16 parameters, the description compensates well by naming almost every input in human terms: "corner radius"→borderRadius, "controls"→showControls, "voice on/off"→voiceEnabled, "chat on/off"→chatEnabled, "Modern look (background, glass, font, panel side, presenter bubble, voice visual)"→modern.*, "button texts"→texts. It stops short of value semantics (hex colour formats, enum choices) and of noting which of the five colour fields map to backgroundColor/textColor/buttonColor/buttonTextColor/progressColor.

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 enumerates the concrete settings this tool controls (theme, colours, corner radius, controls, autoplay, voice/chat toggles, modern-look sub-options, transition, button texts), which makes the resource and effect identifiable at a glance. It does not explicitly name the neighbouring presentation tools (set_presentation_slides, set_presentation_cta, set_presentation_voice) to draw a boundary, though the enumerated field list implicitly separates it.

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?

"Only what you pass changes" is a genuine usage rule for partial updates, and "Free" tells the agent there is no credit cost to calling it. However, there is no statement of when to prefer this over set_presentation_voice/set_presentation_cta, no prerequisites (the id must come from list_agents, only visible in the schema), and no exclusions.

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