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

With no annotations, the description carries the full burden and does so: it discloses that this changes real authoritative state, that the old server record is retained as a copy pointing at the new home, that the reply is an idempotent outcome carrying the new revision, and that a stale revision or changed source home is refused rather than overwriting a concurrent move. Concurrency, idempotency and dry-run side-effect behavior are all covered.

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?

Purpose is front-loaded in the first clause and each following sentence covers a distinct concern (prerequisites, retained copy, refusal/idempotency, dry-run). It is dense and slightly long, but no sentence is redundant; a marginal trim of the elicitation clause would tighten it.

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 7-parameter, state-changing tool with no annotations, the description plus the existing output schema covers what an agent needs: where to obtain preconditions, what is mutated, what is retained, how conflicts are refused, and how dry-run/elicitation works. Return-value details are rightly left to the output 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?

Schema coverage is 71%, so the schema documents several parameters already, but the description adds real semantic weight: baseRevision/sourceHome must be quoted from the current design read, operationId exists to make retries idempotent, targetHome is the new home, and dryRun validates without changing anything. It leaves designId and token semantics to the schema, which handles them.

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 (move) and resource (a design's canonical home) with explicit scope: between this server and a repository checkout. It is clearly distinct from siblings like ui_builder_get_design (named as the source of truth) and ui_builder_rename_design (a different kind of mutation).

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 explicit prerequisites (quote the exact baseRevision and sourceHome from ui_builder_get_design, supply a stable operationId, name targetHome) and an explicit when-to-use rule: call first with dryRun: true unless the person already chose the move. It also names the alternative surface (form elicitation when supported).

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