Chain Check (x402)

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

With no annotations, the description carries the full burden and adds important behavioral context: it is a paid lookup costing $0.01 USDC on Base via x402. It also discloses the malicious-address flag categories, though it does not explicitly state read-only behavior or rate limits.

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?

The description is a single front-loaded sentence with no wasted words. Capability and payment model are communicated efficiently.

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 two-parameter lookup tool, it covers the core purpose and payment mechanism well. Since no output schema exists, a brief note on the returned fields or bidirectional behavior would improve completeness, but the essential information is 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 description coverage is 100%, so the baseline is 3. The description does not add meaning beyond the schema for either parameter: q is already described as an address or ENS name, and x402_payment is fully documented in 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?

The description states a specific verb and resource: ENS-to-address (and reverse) resolution plus malicious-address flagging. It also names the flag categories (phishing, scam, sanctions, mixer), making its purpose distinguishable from siblings like token_risk or wallet_report.

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 by the stated capabilities, but there is no explicit guidance on when to choose this over siblings such as token_risk or wallet_report. No exclusions or alternative-tool routing are provided.

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

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

With no annotations, the description carries the full load and does disclose the important non-obvious behavior: a $0.02 USDC payment on Base via x402. It does not say whether the call is read-only, what happens on unpaid first call, whether results are cached, or how the flags are surfaced in the response.

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 dense sentences, front-loaded with the capability and followed by the commercial constraint. Every clause carries information; nothing is redundant.

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?

No output schema and no annotations, so the description bears the burden. Enumerating the flag categories is helpful, but it never describes the shape of the result (score? per-flag booleans? severity?) or the two-step payment handshake, leaving real gaps for a paid tool.

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 67%; the chain parameter already lists supported values and x402_payment explains the omit-to-get-terms flow. The description adds only the payment amount/asset, and says nothing about the undocumented 'address' parameter (e.g., that it must be a verified contract address).

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+resource ('Smart-contract risk scan') and enumerates the check categories it covers (proxy/admin, owner, mint, blacklist, pause, fee-change, trading toggle). The 'contract' framing inherently distinguishes it from token_risk and address_label, though it never names those siblings 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?

No statement of when to reach for this scan versus token_risk or wallet_report, and no preconditions beyond the cost. The agent must infer that this applies to a deployed contract address rather than a token or wallet.

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

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

With no annotations, the description carries the full burden, and it does disclose two important behaviors: it is a paid endpoint ($0.005 USDC on Base) using the x402 protocol. However, it says nothing about rate limits, caching/freshness of 'live' data, or what happens when payment is absent — the latter only appears in the schema parameter text.

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 short sentences, front-loaded with what the tool returns and backed by cost/payment info; no filler. Slightly telegraphic, but every clause carries information an agent needs before paying for a call.

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?

There is no output schema, so the description must convey return shape, and it partly does (per-chain gas, USD transfer/swap cost, cheapest chain). It omits which 7 chains, the response structure, and the two-step pay-first flow, which for a paid endpoint is a meaningful gap.

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% and there is only one optional parameter, so the schema already fully documents the x402_payment payload and the omit-to-receive-terms flow. The description adds only the price and chain, matching the baseline of 3 for a single well-documented parameter.

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 the resource precisely (live gas on 7 EVM chains) and the specific outputs (USD cost of transfer/swap, cheapest chain), which tells an agent exactly what it gets back. It distinguishes itself from siblings like pricing and token_risk by being gas-focused, though it never uses a verb like 'fetch' or 'return'.

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?

There is no explicit when-to-use statement, no exclusions, and no named alternative among siblings (e.g. pricing) that might also return cost data. The only usage-adjacent signal is the payment note, which is about mechanics rather than about choosing this tool.

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

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

With no annotations, the description carries the full burden, and it does disclose two useful traits: the call itself is free, and payments for listed tools run over x402 with USDC on Base. It does not say whether the tool is read-only (implied by "lists"), what permissions if any are needed, or anything about response size/freshness.

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 short sentences, front-loaded with the most decision-relevant fact ("Free.") before the content scope. No filler and nothing repeated from structured fields.

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 zero-parameter, no-output-schema listing tool this is close to sufficient: the agent knows what it returns (tool names, prices, payment instructions). A little more on the shape of the price data or on how the x402 payment step actually works would close the remaining gap.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate. Baseline 4 applies; the description correctly doesn't waste words on inputs.

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 gives a concrete verb and object set: it lists the available Chain Check tools, their prices, and payment methods. That distinguishes it from every sibling (address_label, contract_scan, gas_snapshot, token_risk, wallet_report) which are all analysis tools. It stops just short of a 5 because it doesn't explicitly frame itself as the catalog/meta tool relative to those siblings.

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?

"Free." implies an agent can call it without cost concerns, and the listing purpose implies it's the discovery step before calling paid tools, but this is never stated. There is no explicit "use this before/after X" or exclusion of any alternative.

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

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

With no annotations, the description carries the full burden and does disclose the most consequential non-obvious trait: the tool is gated behind a $0.02 USDC payment on Base via x402. It also states the score scale. It stops short of describing latency, caching, or what happens when an unsupported chain is supplied, so it is not fully complete.

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 tight sentences: the capability and its output dimensions first, the payment constraint second. No filler, nothing repeated, and the most decision-relevant facts are 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 3-parameter tool with no annotations and no output schema, the description covers the return value at a high level (0-100 plus factor list) but leaves the actual response shape, factor weighting, and failure modes unexplained. Adequate to attempt a call, not enough to interpret one confidently.

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 67%, in the middle band, and the description adds little parameter-level detail. It implies that 'address' is the ERC-20 token contract (via 'ERC-20 token' in the first sentence) and that payment is part of the flow, but the schema already documents the chain values and the x402 payload.

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 resource and output ('ERC-20 token risk score 0-100') and enumerates the exact risk vectors checked (honeypot, taxes, mint, hidden owner, blacklist, LP lock, top holders). That is far more concrete than a sibling like contract_scan, though it never explicitly says how it differs from that sibling.

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?

Use is implied — the list of rug-pull vectors makes it obvious this is a pre-trade due-diligence check — but the description never says when to choose this over contract_scan or address_label, nor any preconditions beyond the payment note. No exclusions are stated.

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

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

No annotations exist, so the description carries the full burden. It does disclose a significant behavioral trait — the tool is paywalled at $0.01 USDC on Base via x402 — which an agent must know before calling. It omits other important behaviors: the actual list of 7 chains, what happens on an unpaid first call, error/retry semantics, and rate limits.

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 the tool returns comes first, the payment precondition second — the ordering matches what an agent needs to decide and then execute.

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?

With no output schema, the description usefully enumerates return contents (balances, tx counts, detection), and the paywall is stated. The x402 handshake is covered by the schema field description. The main shortfall is the absence of the concrete chain list and any error behavior, which matter for a multi-chain paid 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 coverage is only 50%: x402_payment is well documented in the schema, but address has no description at all. The description partially compensates by framing the tool as an 'EVM wallet' report over 7 chains, which implies address must be an EVM-format address, but it gives no format, case, or ENS guidance. This is adequate but leaves a real gap.

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 resource and enumerates exactly what the report contains: balances (native/USDC/USDT) across 7 EVM chains, tx counts, and contract/EIP-7702 detection. That is far more specific than a tautology. It stops short of 5 because it doesn't distinguish itself from siblings like contract_scan or token_risk, which overlap with the 'contract detection' and risk-adjacent outputs mentioned.

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?

'Paid $0.01 USDC on Base via x402' plus the schema note 'Omit to receive payment terms' implies a two-step payment handshake, so usage context is partially conveyed. However, there is no explicit when-to-use guidance relative to address_label, contract_scan, or token_risk, and no statement of when this tool is the wrong choice.

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