set_box

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

No annotations are provided, so the description carries the full burden. It discloses conflict behavior, the fact that the handler is not executed on stale versions, the uncertainty caused by communication errors, and the no-retry policy. This is strong behavioral transparency for a mutating tool.

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?

The core operation and size constraint are front-loaded, and every instruction is relevant to correct usage. Some redundancy exists with the baseRevision property description in the schema, and the mixed English/Japanese phrasing slightly reduces readability.

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 no-output-schema, no-annotation mutation tool with five parameters, the description is unusually complete: operation, constraints, conflict handling, error uncertainty, and a recommended next step. It omits only explicit success-return details and exact coordinate semantics, which are relatively minor.

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 only 20%, so the description compensates by stating canvas bounds and the 64×64 minimum size. baseRevision semantics are explained in detail. It does not explicitly define coordinate origin or maximum x/y/width/height values, but it adds meaningful context beyond 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 and resource: 'Move or resize the box within a 720×480 canvas.' This clearly identifies the operation and target, and differentiates it from siblings like set_text and set_settings without ambiguity.

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?

Provides explicit procedural guidance: pass the observed revision string, check current state with await_change first, do not auto-resend on a newer revision, and re-evaluate intent against the latest doc. It also states when not to execute the handler, namely when the version has changed.

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