the402 x402 endpoint directory

Normalize caller-supplied positive price ticks to fixed decimals — call when rounding caller-supplied price ticks to f

Encode bounded UTF-8 text to hex or inspect hex byte length without RPC — call when encoding bounded UTF-8 to hex or i

Check whether an address already matches its EIP-55 checksum form — call when verifying an address already matches EIP

Validate Bitcoin-base58 alphabet membership for local address hygiene — call when checking Bitcoin-base58 alphabet mem

Index ABI type frequency for planning encodings without performing eth_call — call when indexing ABI type frequency be

Extract the 4-byte function selector from calldata hex — call when reading the 4-byte selector from calldata. Use for

Look up a static chain id to network name table without live RPC — call when mapping a static chain id to a network na

Validate a 32-byte transaction hash format and normalize casing — call when validating a 32-byte transaction hash form

Produce or validate an EIP-55 checksummed EVM address without network calls — call when producing or checking EIP-55 c

Convert between wei and ether using fixed 1e18 scaling without RPC — call when converting wei↔ether with fixed 1e18 sc

Canonicalize and validate even-length hex strings with optional 0x prefix — call when normalizing even-length hex for

Gate a workflow on an explicit boolean check map before side effects — call when a boolean checklist must pass before

Cap desired worker concurrency against a hard limit and queue depth signal — call when clamping desired parallelism ag

Recommend a batch size from item count, hard cap, and average item bytes — call when batching micro-calls under item a

Derive closed, open, or half-open circuit state from failure and cooldown inputs — call when deciding closed/open/half

Split a total timeout into per-step budgets after reserved overhead — call when carving a parent timeout into per-step

Compute a stable topological order for workflow nodes and report structural cycles — call when ordering workflow nodes

Score task priority from urgency, impact, and effort into an ordered band — call when ranking agent tasks from urgency

Create a stable SHA-256 idempotency fingerprint from a scope and canonical payload without storing state — call when w

Build a bounded exponential retry delay schedule with a hard delay cap — call when configuring exponential backoff bef

Allocate a total millisecond budget across ordered workflow steps using optional weights — call when you must split on

Measure top-account and top-three revenue concentration without returning account values. Use it as a bounded prefligh

Calculate descriptive conversion lift for control and treatment. Use it as a bounded preflight or analysis step inside

Calculate break-even units from fixed cost and contribution per unit. Use it as a bounded preflight or analysis step i

Calculate LTV-to-CAC ratio with a bounded health heuristic. Use it as a bounded preflight or analysis step inside an e

Calculate per-cohort and weighted retention from bounded cohorts. Use it as a bounded preflight or analysis step insid

Calculate step and overall conversion from ordered funnel stages. Use it as a bounded preflight or analysis step insid

Calculate static cash runway from cash and monthly burn. Use it as a bounded preflight or analysis step inside an ente

Calculate gross profit, gross margin, and profitability. Use it as a bounded preflight or analysis step inside an ente

Calculate the minimum price required for a target gross margin. Use it as a bounded preflight or analysis step inside

Calculate gross profit and margin from per-unit price and cost. Use it as a bounded preflight or analysis step inside

Identify unbounded dependency declarations before an agent installs them. Use it as a bounded preflight or analysis st

Audit password policy for length, breached-secret checks, and MFA. Use it as a bounded preflight or analysis step insi

Score the presence of five high-value browser security headers. Use it as a bounded preflight or analysis step inside

Audit JWT claim names, expiry, and identifiers at an explicit reference time without returning claim values. Use it as

Audit a Set-Cookie value for Secure, HttpOnly, and SameSite controls. Use it as a bounded preflight or analysis step i

Check a redirect target against an exact hostname allowlist. Use it as a bounded preflight or analysis step inside an

Screen untrusted text for common cross-site scripting signals without echoing it. Use it as a bounded preflight or ana

Screen untrusted text for common SQL-injection signals without echoing it. Use it as a bounded preflight or analysis s

Screen a URL for private hosts, unsafe schemes, and embedded credentials. Use it as a bounded preflight or analysis st

Recommend a semantic-version bump from explicit change signals. Use it as a bounded preflight or analysis step inside

Apply bounded top-level JSON Merge Patch semantics for integration planning. Use it as a bounded preflight or analysis

Index named GraphQL queries, mutations, and subscriptions. Use it as a bounded preflight or analysis step inside an en

Compare requested OAuth scopes with the minimum required scopes. Use it as a bounded preflight or analysis step inside

Produce a signature, idempotency, acknowledgement, and retry plan for webhooks. Use it as a bounded preflight or analy

Classify an HTTP outcome for retry and remediation without returning its body. Use it as a bounded preflight or analys

Compare expected and actual top-level response fields and value types. Use it as a bounded preflight or analysis step

Canonicalize an HTTP request, remove credentials, and derive a stable fingerprint. Use it as a bounded preflight or an

Infer a bounded cursor, link, or page pagination plan from a response envelope. Use it as a bounded preflight or analy

Normalize common HTTP rate-limit and retry headers. Use it as a bounded preflight or analysis step inside an enterpris