set_variable_mode

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

With no annotations, the description carries the full behavioral burden. It usefully discloses recurse's default of true and the root-only override, plus the implicit whole-page fallback, but says nothing about whether the change is stateful/destructive, whether it requires a loaded file or collection, or how it interacts with already-applied modes.

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 a front-loaded 'Theme switch:' label and zero filler; the scoping options are enumerated compactly. Nothing could be cut without losing information.

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 5-parameter mutation tool with no annotations, no output schema, and 0% schema documentation, the description covers most of what an agent needs but leaves collectionId unexplained and omits any note on effect or return. Adequate but with clear gaps.

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 description coverage is 0%, so the description must compensate. It does well for modeId (id or exact mode name), nodeIds, rootNodeId and recurse, but it never mentions the collectionId parameter, which matters for disambiguating a mode name that may exist in multiple collections.

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 up front ('Theme switch: set the variable mode for one or many nodes'), so the operation is unambiguous. However, it never distinguishes itself from the near-identical sibling set_node_explicit_variable_mode, nor from create/rename/delete_variable_mode, leaving an agent to guess which one applies.

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 explains how to choose a scope (nodeIds, rootNodeId, or the whole current page), which implies when each targeting option is appropriate. It gives no explicit guidance on when to use this tool versus the sibling set_node_explicit_variable_mode, and states no preconditions.

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