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

Beyond the annotations (readOnly, openWorld, non-destructive), the description discloses meaningful behavioral traits: the cost (five or six read requests), the partial-failure semantics ('if that lookup fails the reply says so instead of failing'), and the underlying endpoints. This is exactly the extra context annotations cannot provide.

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?

The key fact ('One booking with everything attached') is front-loaded and the description is compact. The endpoint list at the end is slightly implementation-detail heavy but still supports the request-count claim and does not bloat the text unreasonably.

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 an aggregate GET with no output schema, the description sufficiently enumerates the included entities (calendar events, line items, payments, invoices, guest contacts) and explains failure behavior. It does not describe the response structure (e.g., arrays vs nested objects), but that is a minor gap for an agent deciding to call it.

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?

With a single parameter and 100% schema description coverage, the schema already defines booking_id as a UUID. The description adds no additional parameter-level meaning, which is correct for a baseline-3 case where the schema does the heavy lifting.

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?

The description states a specific verb and resource ('One booking with everything attached') and enumerates the attached entities, making clear this is an aggregate read rather than any of the many list_* siblings. It is distinguishable from list_bookings and the individual resource list tools 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 aggregate framing and the note that it costs 'Five or six read requests' imply when to use it (when you need the full booking with all attachments in one call). However, it never explicitly names an alternative or states when not to use it, so it falls short of a full when/when-not contrast.

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