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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the mutation profile is conveyed structurally. The description adds valuable non-structural context: it must run before placement generation, and Amazon verifies the submitted dimensions on receipt. It does not explain that the write is gated by a preview/confirm_id flow, but the schema covers that parameter.

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?

Front-loaded with 'ACTION' and the core resource, then layers ordering and user guidance. Dense but every clause adds operational value; 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 nested-array mutation with no output schema and 50% schema coverage, the description covers purpose, sequencing, and input expectations. The two-step confirmation behavior and response handling remain implicit, but the necessary context to call it correctly is present.

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 50%, and the description partially compensates by explaining what 'groupings' carries: CM dimensions, KG weight, identical-box quantity, and SKU+quantity content with the content_source exception. It adds no detail on confirm_id or account_id beyond the schema. Adequate but not rich.

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 (Registra/set) and resource (the BOXES of the FBA inbound plan), and ties itself to a clear phase (after packing confirmed, before placement options). An agent can distinguish it from create_inbound_plan and generate_inbound_options without inspecting the schema.

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?

Explicit sequencing guidance: it is a mandatory step before generating placement options, and it instructs the agent to ask the user for real dimensions/weight. No explicit when-not condition, but the context and prerequisite are clearly stated.

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