Set the screenshot theme

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

Annotations already declare idempotent=true and destructive=false, so the safety bar is low. The description adds genuinely useful context beyond them: the change applies globally to every slide rather than one, and devices render 'in store order' (an ordering side effect the schema does not convey). It stops short of saying whether omitted fields are preserved or reset.

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?

One dense but well-ordered sentence: the affected scope first, the settable facets second, the follow-up render call last. The parenthetical value lists are compact. It is list-heavy but no clause is 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 3-parameter tool with a nested theme object and no output schema, the description covers every theme facet and the device list, plus the render follow-up. The one gap is update semantics — whether unspecified theme keys are left untouched or reset — which matters for a partial-update mutation.

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 67%, so the schema carries much of the load, but the description adds meaning the schema lacks: 'backgroundEnd (null = solid)' clarifies the nullable gradient field, 'accent (highlighted words)' disambiguates accent from textColor, and 'in store order' explains device array semantics. Font/position/frame enum values are restated from the schema, which is redundant but harmless.

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') and resource ('the look shared by every slide') and then enumerates the exact settable facets plus the device list. It is clearly distinguished from screenshots_edit_slide (per-slide) and screenshots_render (the follow-up render step), which it names.

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?

The description gives an explicit sequencing instruction: set the theme here, then call screenshots_render. The phrase 'any subset' signals partial updates are allowed. It does not state when to prefer this over screenshots_edit_slide or screenshots_import_store, so the routing guidance is good but not exhaustive.

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