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

Annotations declare the safety profile (readOnly false, destructive false, idempotent true), but the description adds real context: no wallet connection, no signing, no broadcasting, no fund movement, and a secrecy obligation for the token. It still does not say what the pending order's lifetime is or what happens if the quote is never paid.

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, front-loaded with the core action, then the non-actions, then the safety precondition. No filler and every sentence carries distinct information.

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 10-param, 9-required creation tool with no output schema, the description adequately covers the return ('exact USDC payment coordinates') and the credential/approval preconditions. The main gap is that most individual parameters remain unexplained for an agent assembling a call.

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 only 30% across 10 parameters, so the description must compensate and largely does not. It implies access_token secrecy and that payer_address supplies the sending wallet, but email, password, quantity, network, target_url, anchor_text, and idempotency_key gain no meaning beyond the schema.

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: 'Create one pending order and return exact USDC payment coordinates' tells the agent exactly what is produced (an order plus payment coordinates). It does not name any sibling (check_payment, submit_payment_proof, get_order_status), so routing among the payment family is left to inference.

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?

Boundary statements ('does not connect a wallet, sign, broadcast, or move funds') and 'obtain the wallet owner's approval before payment' imply this is the pre-payment quoting step, but no sibling is named as the follow-up (e.g. submit_payment_proof). Usage is implied rather than explicit.

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