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

With annotations already declaring non-read-only, non-destructive, non-idempotent behavior, the description adds real value beyond them: "Sends nothing to anyone and charges nothing" rules out email and billing side effects, and "POST /products" pins the operation. It stops short of noting duplicate-id behavior, which is the one trait (idempotentHint=false) an agent might still misjudge.

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?

Three short sentences, zero filler, front-loaded with the "WRITE:" signal and then the side-effect clarification. Every clause earns its place.

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 create tool with full schema coverage, no output schema, and complete annotations, the description covers purpose, inputs, side effects, and endpoint. Nothing an agent needs to invoke 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 description coverage is 100%, so both parameters are already documented. "Your own id plus a name" merely re-emphasizes what the schema says ("Your unique product id."), adding no syntax, format, or uniqueness constraint beyond it. Baseline 3 applies when 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?

Specific verb+resource ("register a product record") with the exact inputs named ("your own id plus a name") and the business rationale ("so orders can reference it"). The order-reference framing implicitly separates it from siblings like create_order or create_field, so an agent can place it without opening the 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?

It gives clear context for when to call it: to register a product that later orders will reference. However, it never states the inverse condition (e.g. use update_product for existing products, or that duplicates are disallowed), so the agent gets positive guidance but no exclusions or named alternatives.

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