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

readOnlyHint=true already establishes this is a safe read, and the description usefully adds the cross-channel scope and the content-type breakdown. It does not mention pagination behavior, return shaping, or rate limits, but for a read-only list tool with annotations carrying the safety profile, this is reasonable.

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?

Front-loaded with the core action, then scoped via a compact em-dash clause and a filter clause, closing with the underlying endpoint. No wasted sentences for the amount of information conveyed.

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 9-parameter filter tool with no output schema, the description covers what the messages contain and the filtering surface, which is enough for correct invocation. It stops short of explaining response shape or pagination details, though the page parameter's schema note partly compensates.

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 89%, so the schema already documents the parameters well, establishing a baseline of 3. The description names filter dimensions that map onto parameters but adds no format or syntax detail beyond what the schema provides.

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 (read/list) and resource (booking messages), then enumerates the exact content types returned (guest messages, host replies, internal notes, system messages) and the channels covered. This clearly separates it from siblings like beds24_send_booking_message and beds24_mark_messages_read without needing to open their schemas.

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 filter enumeration (booking, property, room, read/unread, source, age) implicitly signals the retrieval use cases, but there is no explicit when-to-use statement nor any routing to alternatives such as mark_messages_read or send_booking_message. Adequate but leaves the agent to infer selection.

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