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

Goes well beyond the annotations, which only say readOnly/openWorld/non-idempotent. The description discloses pricing (0.10 USDC per call on Base via x402 exact), the shared quota (10 signed-wallet free calls per rolling 30 days), the required X-Wever-Wallet-Proof binding to exact JSON arguments and route, the per-source status semantics (found / nothing found / unavailable / not run), and the Ed25519 signed receipt.

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-loads the purpose, then inputs, then sources, then payment and auth mechanics — a sensible order for a paid tool. It is dense but nearly every clause carries operational weight; only the closing human-page link is incidental rather than task-relevant.

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-parameter, paid, open-world read tool with no output schema, the description supplies everything needed: what the return value contains, how source statuses are reported, that a signed receipt accompanies it, the payment and quota model, the header-proof requirement, and pointers to the contract and human docs.

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% and the single parameter already documents accepted identifier forms with pattern and length bounds. The description restates the same accepted inputs (agent ID, mailbox ID, registered name, service/operator name, domain, URL) rather than adding new meaning, so the baseline 3 applies.

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 and resource: 'one-call diligence brief on an agent or service', then enumerates exactly which sources it fuses (free agent directory listing, Wever x402 index entry, Agent Trust Check facts, evidence summary). This implicitly distinguishes it from single-source siblings like wever_agent-trust-scorecard, data-evidence-check or wallet-activity-brief, though no sibling is named explicitly.

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 context is implied by enumerating accepted counterparty identifiers and by framing the tool as a combined brief, so an agent can infer 'use when you need multi-source diligence on one counterparty'. However, there is no explicit when-not-to-use guidance and no routing to alternatives such as agent-trust-scorecard (single-fact trust) or mcp-diligence-rail (deeper diligence), which is the main gap.

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