DB x402-layer
x402-layer helps agents pay for APIs with USDC, deploy monetized endpoints, manage credits/webhooks/marketplace listings, and handle wallet-first ERC-8004 registration/discovery/management/reputation on Base, Ethereum, Polygon, BSC, Monad, and Solana. Optional credentialed flows may use private keys, Solana signer keys, endpoint API keys, PATs, AWAL, or OWS depending on the exact runbook; read-only discovery requires no secrets. Only ask for or use privileged credentials after choosing a runbook that actually needs signing or owner-scoped writes. Use this skill when the user asks to "create x402 endpoint", "deploy monetized API", "pay for API with USDC", "check x402 credits", "consume API credits", "list endpoint on marketplace", "buy API credits", "topup endpoint", "browse x402 marketplace", "set up webhook", "receive payment notifications", "manage endpoint webhook", "verify webhook payment", "verify payment genuineness", "integrate crypto payments into my app", "add USDC payments to my platform", "sell with x402", "build a paywall with webhooks", "register ERC-8004 agent", "register Solana 8004 agent", "submit on-chain reputation feedback", "rate ERC-8004 agent", "use World AgentKit", "unlock human-backed agent wallet discount", "check if an endpoint has an AgentKit benefit", "add API schema to endpoint", "document my API routes", "auto-detect OpenAPI schema", "open support chat", use "Coinbase Agentic Wallet (AWAL)", "OpenWallet", "OWS", "openwallet.sh", or use optional Singularity MCP access with a dashboard PAT to manage x402 Singularity Layer operations on Base, Ethereum, Polygon, BSC, Monad, or Solana networks. Also use this skill to stake $SGL agentically: "stake SGL", "stake $SGL", "unstake SGL", "claim staking rewards", "check my staking position", "stake to run a node", "agentic staking" — sign and submit on-chain Solana staking transactions with a wallet keypair.
As a process B 68/100 · Nearly there — weak spots: result and completion, inputs and preconditions, running it twice
What is at stake
Medium-severity findings: the skill is probably honest, but read what alarmed the scanner.
Below is the worst case for this category. The finding here is medium: the guard saw a sign, not a proof.
The instructions or scripts send data out: environment variables, keys, file contents, chat history. You may never notice, because the agent performs the upload as "part of the task".
If the upload is not needed for the task, remove it: catalogs flag such skills and delist them. If it is needed, name the destination explicitly, say what leaves the machine, and give the user a switch.
Below is the worst case for this category. The finding here is medium: the guard saw a sign, not a proof.
The skill asks for more than the task needs: broad tool access, credential environment variables, binaries. Every extra permission widens the damage from a mistake or a compromise.
Narrow allowed-tools and the variable list to the minimum; replace binaries with readable sources or scripts.
How to improve
- Shorten the description to 1024 characters.
- The SKILL.md body is over 5,000 tokens: move reference detail into references/ and load it when needed.
- Your own cases (evals/evals.json, 4–6 real requests with expected answers): the full check would then run those instead of a model-drafted suite.
- A spec.yaml with trigger phrases and assertions — a behaviour contract for CI; `skilltest init` writes a template.
Guard findings · 17
✓ No critical or high findings
Medium and low: 17
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medium Exfiltration
net-redirectable-api-keyscripts/submit_feedback.py:21Helper sends the API key to a host configured by an environment variable — the key can be redirected to another serverAPI key + configurable base URL from environment
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medium Exfiltration
net-redirectable-api-keyscripts/support_auth.py:20Helper sends the API key to a host configured by an environment variable — the key can be redirected to another serverAPI key + configurable base URL from environment
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medium Exfiltration
net-redirectable-api-keyscripts/support_threads.py:24Helper sends the API key to a host configured by an environment variable — the key can be redirected to another serverAPI key + configurable base URL from environment
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medium Broad scope
meta-broad-allowed-toolsSKILL.md:1Broad tool permissions pre-approved: Bashallowed-tools: Read Write Edit Bash WebFetch
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low Secrets in code
secret-high-entropy-tokenreferences/pay-per-request.md:75High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)"payTo": "0xCD…275",
quoted -
low Secrets in code
secret-high-entropy-tokenreferences/pay-per-request.md:86High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)"payTo": "3rcd…qCx",
quoted -
low Secrets in code
secret-high-entropy-tokenreferences/pay-per-request.md:87High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)"asset": "EPjF…t1v",
quoted -
low Secrets in code
secret-high-entropy-tokenreferences/pay-per-request.md:120High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)"verifyingContract": "0x83…913"
quoted -
low Secrets in code
secret-high-entropy-tokenreferences/payment-signing.md:15High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)"verifyingContract": "0x83…913"
quoted -
low Secrets in code
secret-high-entropy-tokenreferences/staking.md:7High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)- **Program:** `3zCh…aBC` (Solana mainnet)
quoted -
low Secrets in code
secret-high-entropy-tokenreferences/staking.md:8High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)- **Token:** `$SGL` `5c4H…AGS`
quoted -
low Risky intent
intent-wallet-secretsscripts/consume_product.py:17Handles crypto-wallet secrets (seed / mnemonic / private key) — a classic stealer target (quoted — discussed, not commanded)PRIVATE_KEY - Your EVM wallet private key (Base network)
quoted -
low Secrets in code
secret-high-entropy-tokenscripts/consume_product.py:37High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)USDC_ADDRESS = "0x83…913"
quoted -
low Secrets in code
secret-high-entropy-tokenscripts/solana_signing.py:309High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)token_program_id = Pubkey.from_string("Toke…5DA")quoted -
low Secrets in code
secret-high-entropy-tokenscripts/solana_signing.py:310High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)ata_program_id = Pubkey.from_string("ATok…knL")quoted -
low Secrets in code
secret-high-entropy-tokenscripts/solana_signing.py:311High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)usdc_mint_default = "EPjF…t1v"
quoted -
low Secrets in code
secret-high-entropy-tokenscripts/wallet_signing.py:23High-entropy token-like string (may be an id, hash or a credential) (quoted — discussed, not commanded)USDC_ADDRESS = "0x83…913"
quoted
Files scanned: 47. Evidence is masked. Grey chips explain why severity was lowered.
Against the Agent Skills spec
- error
description-longdescription is 1909 chars, limit 1024 - warning
body-longSKILL.md body ≈ 6371 tokens (recommended < 5000); move details to references/ - note
description-budgetdescription takes 1909 of the ~15000-char shared budget for all skills - note
frontmatter-keyunknown frontmatter key "homepage"
Process rating: all ten parameters 68/100
- 0Result and completion. Does not say what the result is
- 0Inputs and preconditions. Does not say what the process needs to start
- 0Progress reporting. Says nothing while it works
- 30Running it twice. 16 mutating operations with no state check
- 70Execution cost. Instruction body is 6371 tokens
- 100Tools and files. Tools declared in frontmatter
- 100Steps. 70 steps
- 100When it triggers. States when to use and when not to
- 100Failures and branches. 3 branches, has a failure section
- 100Consistency. Name and required fields are in place
- medium Safety rules and hard prohibitions inside a skill: they belong in the system prompt, here they protect nothing
- low 11 top-level sections: this looks like several domains in one skill
Everything here is measured from the skill text rather than judged by a model, so the numbers are checkable. A parameter weighs more when it is a more common reason for the process to stall.
Quality signals
- +4Description does not say when NOT to use the skill (false activations)
- +3Description length 1908: 120–800 characters recommended
- +3Output format is not stated: the model decides each time
- -35 of 31 scripts are never mentioned in SKILL.md
- +1No license
- +2Single-language instructions
- +5Description quotes 39 example trigger phrases
- +4Structure: 43 headings
- +3Step-by-step instructions: 70 items
- +4Has examples (21 code blocks)
- +4Reference files are cited in the instructions (13 of 13)
Quality base 70; lint remarks subtract, signals add up to 100. Result: 48.