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

Annotations already flag destructiveHint=true, so the agent knows this is a mutating, non-undoable send; the description goes further by disclosing the relay mechanics (maker sees plain text from the network account, contact details and links stripped) and derives a hard content constraint from it. It does not state delivery latency, failure modes, or whether a reply can be retracted, so it stops short of a 5.

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, front-loaded with the action and its trigger, then the user-confirmation requirement, then the relay constraint. No sentence restates the tool name or the schema, and the closing warning is placed where an agent will read it before composing the message.

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 two-parameter mutation with no output schema, the description supplies everything the agent lacks: when the tool applies, the confirmation gate, and the sanitization constraint on message content. Nothing required to call it correctly is missing.

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 real semantic weight: 'message' must be the user's own words and must not contain emails, phone numbers, or URLs the answer depends on, which constrains what the agent may put in that parameter. order_id gets no added detail beyond the schema's ord_… hint.

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 (send) plus resource (the user's answer to a maker's question about a UFP order) and ties it to the sibling tool that surfaces the trigger condition (get_order_status). An agent can distinguish this from create_checkout, finalize_quote, and the rest of the order-flow siblings without opening any 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?

Explicitly names the condition that selects this tool ('get_order_status surfaces an open question when one is waiting') and the alternative path to discovery. It also imposes a prerequisite — confirm the answer with the user before sending — which is exactly the kind of routing/authorization guidance an agent needs.

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