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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the write/non-destructive profile is known. The description adds genuinely new information with "Effects: order created in draft", telling the agent the order is not confirmed or fulfilled and that downstream steps are needed. It stops short of noting validation failures (e.g. unknown customer/item) or whether a price override needs approval.

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: what it does, when to use it, when not to, then the resulting state. Zero filler and the distinguishing clause is front-loaded in sentence one.

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 3-parameter mutation with full annotation coverage and full schema coverage, the description supplies the one thing structured fields cannot: the draft outcome and the quote-vs-order decision rule. Nothing essential is missing, though a note on failure modes or the next step (confirm order) would have made it complete.

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% — customer_id, lines, item_id, qty, unit_price and po_ref are all documented in-schema, including the cents/minor-units convention. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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 ("Raise a sales order") plus the key differentiator "directly, without a quote", which cleanly separates it from o2c_create_quote in the sibling list. An agent can pick the right tool without opening either 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?

"Use this for repeat business and phone orders" gives positive selection criteria, and "Anything the customer negotiated should go through a quote instead" gives the explicit exclusion plus the named alternative. Both when-to-use and when-not-to-use are covered.

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