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

The description adds substantial behavior beyond the readOnly/non-destructive annotations: it lists the returned artifact, plan, provenance, missing questions, and non-sending preview, and explicitly rules out connecting to customer systems, reading records, running SQL, scheduling, writing, or sending. This is unusually transparent for a planning tool with no output schema.

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 purpose is front-loaded in the first sentence, followed by return behavior, unsupported-case behavior, schema contract, and safety boundaries. Every sentence carries distinct operational value with 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?

Given the complex nested input schema, absence of an output schema, and existing annotations, the description is complete enough for correct invocation. It explains return contents, unsupported-scope behavior, schema contract adherence, and the non-sending boundary.

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 100%, so the nested request contract is already documented in the schema. The description adds only that the request follows request.schema.json and must be complete, without explaining individual field semantics beyond what the schema provides.

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?

The description states a specific verb ("Build a design") and resource scope ("for intent expansion-account-review") and clarifies that it operates from a complete structured request. It is clearly distinguishable from the research/search/compare/update siblings, though it does not explicitly name those alternatives.

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?

It clearly states the supported intent and what happens for unsupported intents/adapters, giving useful when/when-not context. It does not explicitly route the agent to sibling tools for adjacent tasks, so it falls short of full alternatives guidance.

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