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

Annotations only declare the generic mutation profile (readOnly=false, destructive=false, idempotent=false), so the description's disclosure of business effects adds real value: no-show frees the slot and settles payment under the owner's no-show rule with tips always returned, while completed counts in client history. It does not address re-invocation or permission requirements, so it falls short of a 5.

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 tight sentences: the core action and its valid statuses are front-loaded, followed by the differentiating effects of each status. No filler or restated boilerplate.

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 two-parameter mutation with annotations but no output schema, the description covers the action, the id source, and the side effects of the meaningful statuses. Minor gaps remain around permissions and re-invocation behavior, but nothing essential for calling it correctly is missing.

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 coverage is 0%, so the description must carry the load, and it does: it identifies the id as coming from my_schedule and gives operational meaning to the enum values (no_show frees time and settles payment; completed counts in history). The 'confirmed' status is left without any semantic explanation, which keeps it out of 5 territory.

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 ('Mark'), the resource ('an appointment'), and the exact set of terminal statuses, plus where the id comes from ('my_schedule'). This clearly separates it from siblings like cancel_appointment, move_appointment, and book_appointment 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?

It names the source of the id ('id from my_schedule') and explains the consequences of the two consequential statuses, which effectively tells the agent when no_show vs completed applies. It stops short of explicit when-not guidance or naming the cancel/move siblings as alternatives for other outcomes.

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