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

The readOnlyHint annotation already establishes the safe read profile, and the description goes further by disclosing exactly what data the call returns (contact details, next/previous booking, cancellation and no-show counts, membership, store credit). It also cites the underlying Bookeo endpoint, adding useful behavioral context. It does not discuss error behavior for missing ids or whether the read is cached.

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 sentences with zero filler: the return contents come first, the API reference last. The scope verb leads the sentence, so the agent reads the essential information immediately.

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, the description appropriately compensates by listing the returned fields, and a single required parameter keeps the surface simple. Missing only exclusions against sibling tools for a fully complete picture.

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?

Only one parameter ('id') exists and the schema already describes it at 100% coverage ('The customer id.'). The description adds no format, prefix, or lookup semantics beyond the schema, so the baseline of 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 ('Get one customer') and enumerates the payload contents (contact details, bookings, cancellations/no-shows, membership, store credit). The word 'one' implicitly contrasts with the list_customers sibling, though it never names the alternative.

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?

Usage is only implied: retrieving a single customer by id versus the sibling list_customers or list_customer_bookings. There is no explicit when-to-use guidance or stated prerequisites for choosing this tool over its siblings.

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