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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds that the output is 'exact machine steps' with specific protocol details (x402 V2, Solana USDC), which is useful context, but it doesn't disclose return format or whether steps expire. Marginal value beyond 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?

Single, well-formed sentence with zero filler and the core purpose front-loaded. Nothing to trim without losing meaning.

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 1-parameter read-only tool with annotations covering safety, the description is nearly complete. It could be improved by explicitly routing to/from build_purchase_request, but it adequately tells an agent what it gets back and under what protocol. No output schema exists, so explaining the 'exact steps' return is helpful and present.

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 100% with a clear enum of product IDs, so the schema carries parameter semantics. The description adds only that it operates on 'one InstaVeil product', which is already implied; no new constraints or format hints are provided. Baseline 3 is 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 (Return) and a precisely scoped resource (exact machine purchase steps for one InstaVeil product via x402 V2 and Solana USDC). It's clearly differentiated from siblings like get_product (catalog details) and build_purchase_request (constructing a request).

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?

Implied usage is that you call this after identifying a product you want to purchase, but the description never explicitly says when to use this versus build_purchase_request, which is the nearest sibling and could confuse an agent. It names no alternative and gives no exclusions.

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