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

Annotations already declare read-only, idempotent, closed-world behavior, so the safety profile is covered. The description adds a genuinely useful non-annotation trait: it is a paid endpoint (300 sats or US$0.25 USDC per call), which affects how an agent should invoke it. It still omits failure modes and rate/quotas.

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 sentences, zero filler. What it screens comes first and the cost constraint second, so the most decision-relevant content is front-loaded.

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 single-input, paid, read-only lookup with a fully documented schema and no output schema, the description supplies enough: scope of screening and price/payment context. It could say more about what the result contains, but return values are largely inferable from the listed signal categories.

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 address format, the l402 token/preimage flow, and the pay_with enum are all already documented in the schema. The description adds no parameter-level meaning beyond that, which is the expected baseline when the schema does the work.

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 (Screens) plus resource (one Bitcoin address) and an enumerated set of risk signals (OFAC, ransomware lists, ownership clusters, sweeper bots, laundering patterns). This clearly separates it from market/geopolitics siblings, though it never explicitly contrasts with the closest sibling, watch_bitcoin_address, which also targets addresses.

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: call this to risk-screen a single address. There is no explicit when-to-use vs watch_bitcoin_address (one-shot screening vs ongoing monitoring), no stated prerequisites, and no exclusions. The pricing note hints that this is a paid per-call lookup but does not guide tool selection.

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