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

Beyond the readOnlyHint and idempotentHint annotations, the description discloses meaningful behavior: dates are business days from today in Central time, the standard estimate includes proof/production/transit, rush skips the proof wait, and rush starts same business day only when artwork arrives before noon Central. This goes well beyond the structured annotations.

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 description is three sentences with no filler. It front-loads the main outcome, then covers shipping-lane input, date calculation basis, and the rush rule efficiently.

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?

Even without an output schema, the description tells the agent what the call returns (standard date and rush date, if offered), how dates are calculated, what is included, and the cutoff behavior. Combined with the fully documented input schema, an agent has enough to invoke the tool correctly.

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 schema already documents both parameters thoroughly. The description adds minor context about using the destination state for a real shipping lane and assuming typical US transit when omitted, but it does not materially change or expand parameter understanding.

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 clearly states the tool estimates when an order placed today would arrive, returning both the standard FedEx Ground date and the rush date when available. This is a specific verb-resource pairing (estimate + delivery dates) that distinguishes it from sibling tools like quote_price, search_catalog, and get_product.

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?

The description gives clear context: use this when you need delivery dates for an order placed today, and provide the buyer's US state for a more accurate shipping lane. It also explains what happens if the state is omitted. However, it does not explicitly name alternatives or state when not to use this tool, so it stops short of a 5.

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