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

Annotations already declare readOnlyHint=true, so the safe read behavior is covered. The description only restates the read operation and HTTP path, adding no auth, error, rate-limit, or return-shape context beyond what is already structured.

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 short sentences with zero wasted words. The purpose is front-loaded and the endpoint detail follows 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?

For a simple read-by-id tool with annotations covering safety and full schema descriptions, the definition is nearly complete. It could mention response shape or not-found behavior, but with no output schema and a straightforward retrieval operation, this is a minor gap.

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 100%, so both id and subdomain are documented in the schema. The description reinforces that id is required for lookup but adds no format or syntax detail beyond the schema, making baseline 3 appropriate.

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 'Fetch' and resource 'appointment', and 'single' plus 'by id' clearly distinguishes it from list, book, and update sibling tools. The HTTP path further reinforces the exact endpoint.

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 implied: use when you have an appointment id and need one record. There is no explicit guidance on when not to use it or which alternative to choose for listing or searching appointments.

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