set_renderer

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

Annotations declare it is a non-read-only, idempotent, non-destructive mutation, and the description adds genuinely new behavior: changes live only in the browser, are lost on reload, do not edit source, are recorded in pending_changes (which feeds code edits), and can be reverted. This is rich disclosure beyond the structured fields.

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 sentences, tightly front-loaded: the critical persistence caveat and recovery path come first, followed by a compact list of adjustable settings. No 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 mutation tool whose safety profile is covered by annotations and which has no output schema, the description supplies the key non-obvious facts (non-persistence, pending_changes, revertability). The remaining gap is documentation of the less obvious parameters like sortObjects and localClippingEnabled.

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 38% (only toneMapping, shadowMapType, outputColorSpace are documented). The description names the setting categories (tone mapping, exposure, color space, pixel ratio, shadows), which recovers some of the five undocumented parameters, but adds no value mappings or formats beyond the schema's own descriptions.

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 ('renderer settings') and enumerates the covered sub-fields (tone mapping, exposure, color space, pixel ratio, shadows). It is distinguishable from the read-only sibling renderer_info, though it does not explicitly contrast with renderer_settings or set_shadow, which also touch these domains.

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 clear operational context: this is a live-preview-only change, not persisted, recorded in pending_changes and undoable with revert_changes. It does not state explicit when-not conditions versus alternatives like set_shadow or renderer_settings, so it falls short of a 5.

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