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

Annotations declare write, non-idempotent, non-destructive, closed-world; the description adds the return value ('customerKey for future orders') and an operational instruction to persist it in AI memory. It does not warn that repeated calls with the same details will create duplicates, which the non-idempotent hint implies but never explains.

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?

Four short sentences, front-loaded with the precondition, then the return value, then the follow-up action. Nothing is redundant with the schema and every sentence changes agent behavior.

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 five-parameter write tool with no output schema, the description covers precondition, return value and key persistence. The only gap is duplicate-registration behavior on repeat calls, which matters given idempotentHint=false.

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% with descriptions and an enum on customerType, so the schema does the heavy lifting. The description restates the collectable fields and the Retail/Wholesale choice but adds no new semantics such as phone format or what constitutes a valid shipping address.

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?

Uses a specific verb and resource ('Register as a GYOTAK customer') and immediately distinguishes itself from the recovery path by stating it returns a new customerKey. It also names the exact field set, so an agent knows precisely what this tool produces versus asking about existing accounts.

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 states the precondition: gather name, phone, address, email and customer type through conversation BEFORE calling. It does not name sibling alternatives (e.g. recover_customer_key for an existing customer), so the exclusion half of the guidance is left to inference.

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