the402 x402 endpoint directory

Expires Header Validate: Expires Header Validate compares Date and Expires timestamps for an explicit cache lifetime f

Age Header Validate: Age Header Validate checks whether an HTTP Age value fits a declared freshness lifetime from boun

Cache Freshness Calculate: Cache Freshness Calculate calculates remaining freshness from response timing metadata from

Cache Control Directive Diff: Cache Control Directive Diff finds added, removed, and changed Cache-Control directives

Cache Control Parse: Cache Control Parse parses Cache-Control directives into typed policy fields from bounded caller-

Compare two bounded caller-supplied DNS record snapshots and return canonical added, removed, and unchanged records. U

Select a reproducible sample without replacement from a bounded caller-supplied list. Use when multiple agents or retr

Validate caller-supplied image delivery metadata before accepting an agent purchase. Checks HTTPS artifact URL, SHA-25

Read JWT exp claim seconds remaining without verifying signature — first-party local utility for agent preflight and p

Mask the middle of a string keeping ends. Call when you redact secrets in logs while keeping identifiable edges. Retur

Split a URL into scheme/netloc/path/query/fragment. Call when you inspect agent-held URLs without network access. Retu

Split host into DNS labels and apex guess. Call when you reason about registrable domains from agent host strings. Ret

Ensure a path ends with /. Call when you normalize directory-style URLs for agents. Returns path with trailing slash f

HTML-escape text for safe embedding. Call when you inject agent text into HTML without XSS. Returns escaped text for $

Deterministic index from seed into [0,length). Call when you need stable A/B assignment without shared RNG state. Retu

Convert seconds to HH:MM:SS. Call when you format agent SLA timers. Returns hms string and seconds for $0.001 USDC via

Convert milliseconds to HH:MM:SS. Call when you format agent durations for humans. Returns hms string and parts for $0

Generate 0..n-1 integers. Call when you need simple index arrays for agent maps. Returns values list and count for $0.

Generate a Python-style range list. Call when you need index sequences for batching without local loops. Returns value

Boolean OR of two coerced values. Call when you combine optional agent success signals. Returns OR result for $0.001 U

Boolean AND of two coerced values. Call when you combine agent preflight gates. Returns AND result for $0.001 USDC via

Boolean NOT of a coerced value. Call when you invert agent gate flags. Returns negated boolean for $0.001 USDC via x40

Compare two numbers (-1, 0, 1). Call when you need ordering decisions between agent scores. Returns cmp result for $0.

Convert mebibytes to bytes. Call when you expand MiB limits into exact byte ceilings. Returns bytes and mib for $0.001

Convert kibibytes to bytes. Call when you expand KiB limits into exact byte ceilings. Returns bytes and kib for $0.001

Convert bit count to bytes. Call when you convert link rates into byte budgets. Returns bytes, bits, whole_bytes for $

Convert byte count to bits. Call when you compare bandwidth or payload budgets in bits. Returns bits and bytes for $0.

Convert Fahrenheit to Celsius. Call when you normalize imperial sensor readings for agent logic. Returns celsius and f

Convert Celsius to Fahrenheit. Call when you normalize weather/agent sensor units. Returns fahrenheit and celsius for

Convert radians to degrees. Call when you display geometry results in degrees. Returns degrees and radians for $0.001

Convert degrees to radians. Call when you feed geometry/trig helpers from degree inputs. Returns radians and degrees f

Map a value from one range into another. Call when you rescale agent metrics between UI and model ranges. Returns mapp

Linear interpolation between a and b by t. Call when you blend scores, progress, or animation parameters. Returns inte

Approximate equality within tolerance. Call when you compare floats from agent math without exact-equality traps. Retu

Check whether a value sits in [min,max]. Call when you preflight budgets, scores, or clamp decisions. Returns boolean

Divide a/b with ok flag when b!=0. Call when you need fail-soft division for agent formulas. Returns value and ok bool

Compute part/whole as percent. Call when you express progress or share for agent dashboards. Returns percent value for

Compute a/b ratio safely. Call when you need conversion rates or price ratios from agent numbers. Returns ratio or nul

Average of a numeric list. Call when you need a mean for agent metrics samples. Returns average and count for $0.001 U

Sum of a numeric list. Call when you aggregate agent-held amounts without a spreadsheet. Returns sum and count for $0.

Maximum of a numeric list. Call when you find ceilings across agent-held samples. Returns max value and count for $0.0

Minimum of a numeric list. Call when you find floors across agent-held samples. Returns min value and count for $0.001

Sign of a number (-1, 0, 1). Call when you branch agent logic on direction without float noise. Returns sign and origi

Ceil a number to integer. Call when you need minimum whole buckets or page counts. Returns ceiled integer value for $0

Floor a number to integer. Call when you need whole units from continuous values. Returns floored integer value for $0

Round a number to N decimal places. Call when you need stable display/math rounding before paying downstream. Returns

Format an integer as an English ordinal (1st, 2nd, 3rd…). Call when you need human-facing ranks or step labels for age

Validate even-length hex (optional 0x). Call when you preflight calldata/hash hex before chain tools. Returns valid bo

Normalize hex with optional 0x prefix and even-length check — first-party local utility for agent preflight and proven

Echo text with length (probe channel 1). Call when you verify x402 pay→deliver wiring with a trivial payload. Returns