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

Beyond annotations (readOnly=false, destructive=false), the description reveals the non-final nature of the prepare step, the need for a LIBRARY-login session, and the expected seat_id source. This is useful behavioral context; it doesn't state side effects like seat-hold expiry, but doesn't contradict annotations.

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 sentences, each carrying distinct information: purpose, confirm_action requirement, seat_id/mcp_session_id mapping, and the direct-reservation alternative. It is front-loaded and compact, though slightly denser than necessary.

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?

The description covers prerequisites and workflow, but because there is no output schema it does not say what the tool returns or how confirm_action picks up the prepared reservation. An agent may not know whether it must pass a prepared action ID or simply call confirm_action with the same session. That missing link prevents full completeness.

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 already documents both parameters (100% coverage), so baseline is 3. The description adds value by mapping seat_id to recommend_library_seats' externalSeatId and giving a concrete example, plus an alternative source (URL number). mcp_session_id is described as needed in the description while schema marks it optional with fallback, a mild wording tension.

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+resource: prepares a central library seat reservation at SSU Campus. It also clarifies that the tool is only a preparation step and does not execute the reservation, distinguishing it from sibling confirm_action and other prepare_* tools.

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?

Clearly tells the agent that final execution requires a separate confirm_action call, and instructs where to source seat_id (recommend_library_seats externalSeatId, or the URL number on oasis.ssu.ac.kr when reserving directly). It doesn't explicitly contrast with prepare_swap_library_seat or prepare_cancel_library_seat, so it falls short of full when-not guidance.

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