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

Annotations already cover safety (readOnly, idempotent, openWorld, non-destructive), but the description adds context they do not: authentication ('Pass required'), the freshness model behind force (probe now vs. reuse a result up to 5 minutes old), and that the output is a signed answer with a pay/caution/avoid recommendation. It stops short of stating failure modes or rate limits, so a 4 rather than 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?

Front-loaded with the critical constraint ('Pass required'), then intent, then Use when / Not for / After in a scannable structure. It is dense and slightly long, but nearly every clause carries operative information rather than filler.

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?

An output schema exists, so return values need no elaboration; the description still flags that the response is a signed recommendation with reasons. Combined with the use-when/not-for/after guidance and the auth requirement, an agent has everything needed to decide, invoke, and sequence this call correctly.

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%, so the baseline is 3, but the description adds meaning beyond the schema: 'Pass required' ties the pass parameter to an auth gate, and 'a fresh probe' explains the semantics of force (probing now rather than reusing a cached result). The url parameter is left to the schema's own description.

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?

The description names a specific action (a pre-spend probe/check) on a specific resource (an x402 endpoint about to be paid) and enumerates exactly what the check composes: fresh probe, parsed quote, payability, payTo on-chain history, seller integrity, scout delivery result, honeypot scan. It clearly separates itself from settled_check ('stale or not enough') and from settled_find_endpoints.

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?

Explicit 'Use when: real money is about to leave your wallet and settled_check was stale or not enough' and 'Not for: browsing (settled_find_endpoints) or endpoints you already verified', plus a named follow-up sequence ('compare pay_to and price ... pay, then call settled_report'). Alternatives and exclusion conditions are stated directly.

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