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

Beyond the annotations (which only say non-read-only, non-idempotent, non-destructive), the description discloses the state machine: partial receipts keep the order open and can be repeated, each receipt is retained with date and note, a full receipt closes it, and two refusal conditions. That is exactly the side-effect and failure-mode detail an agent needs before mutating.

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?

Two dense sentences with no filler; the core action comes first, then the partial/full branch, then the rejection rules. Every clause carries information an agent would otherwise have to discover by error.

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 mutation tool with no output schema, the description covers behavior changes and error cases well. It stops short of saying what the response looks like or whether stock/quantities are updated downstream, a minor gap for a write operation.

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 coverage is 100%, so baseline is 3, but the description adds meaning beyond the schema: it explains the consequence of `partial` (order stays open, can be received again) and that `date` is validated against the order date. Only `id` and `note` semantics are left entirely to the schema.

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?

"Record that an order arrived" names a specific verb and resource, and the title/description together make clear this is the receiving action rather than create/get/list/delete in the purchase_order family. An agent can distinguish it from every sibling without opening a 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?

The partial-vs-full distinction gives explicit guidance on which mode to choose and what each does (stays open vs closes the order). It does not name an alternative tool for cases like checking current status, but the when-to-use condition is unambiguous.

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