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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description reinforces this by framing the call as a preview and adds useful scope context (fulfillability output, 50-item cap), though it says nothing about auth, rate limits, or error behavior.

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?

Three short sentences, the purpose and pre-order timing are front-loaded, and the limit is stated last without filler. Every sentence carries 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?

With an output schema present, the description needn't explain return values, and it covers purpose, timing, and the item cap. Minor gaps remain around the compact-rows/diagnostics flags, but the schema carries those.

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 every parameter including the nested item and destination fields is already documented in the schema. The description only restates the 50-item cap and adds no meaning for include_raw_rows or include_diagnostics, so it earns the baseline.

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 ('Get MCF shipping options and estimated delivery dates') and clarifies its role as a pre-order check, which cleanly separates it from get_mcf_orders and get_fba_inbound_options. It also names what the caller gets back: speeds, fees, and fulfillability.

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?

'before creating an order' gives a clear situational trigger for using this tool. It doesn't name a specific alternative tool or state exclusions, so it falls short of an explicit when/when-not statement.

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