Retrieve a customer

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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds nothing beyond that — notably it does not mention openWorldHint=true, meaning a live API call that can fail or return not-found, which is the one behavior an agent would benefit from knowing.

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?

It is short with no filler, but the brevity is under-specification rather than efficiency — the single sentence does no work beyond naming the operation, so it fails to earn its place as the only guidance provided.

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?

With no output schema and openWorldHint=true, the description should explain that this performs an external lookup and can fail for an unknown id. For a retrieval tool whose result shape is otherwise undocumented, the definition leaves the agent without enough to call it confidently.

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% with a single required id parameter, so the baseline of 3 applies. The description contributes no additional meaning about the id (e.g. format or prefix) beyond the schema's "The object's id."

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?

"Retrieve a customer" restates the title and tool name almost verbatim, adding only a verb+resource pairing. It does not distinguish this from list_customers or create_customer in the sibling set, nor state what identifying information is needed or returned.

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?

No when-to-use guidance is given, and no alternative is named. An agent must infer on its own that this takes a single id and that list_customers is the bulk alternative.

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