System

System functions that do not require special permissions (except diskUsage which requires fs.enabled).

Host information

AssemblyScript

import { sysInfo } from "@luminarys/sdk-as";

const info = sysInfo();
// info.os, info.arch, info.hostname, info.num_cpu

Go

info, err := sdk.SysInfo()
// info.OS, info.Arch, info.Hostname, info.NumCPU

Rust

let info = sys_info()?;
// info.os, info.arch, info.hostname, info.num_cpu

SysInfoResult:

Field	Type	Description
os	string	Operating system: "linux", "windows", "darwin"
arch	string	CPU architecture: "amd64", "arm64", "riscv64"
hostname	string	Machine hostname
num_cpu	int	Number of logical CPUs

Current time

AssemblyScript

import { timeNow } from "@luminarys/sdk-as";

const t = timeNow();
// t.rfc3339, t.unix, t.unix_nano, t.timezone, t.utc_offset

Go

t, err := sdk.TimeNow()
// t.RFC3339, t.Unix, t.UnixNano, t.Timezone, t.UTCOffset

Rust

let t = time_now()?;
// t.rfc3339, t.unix, t.unix_nano, t.timezone, t.utc_offset

TimeNowResult:

Field	Type	Description
unix	int64	Seconds since Unix epoch
unix_nano	int64	Nanoseconds since Unix epoch
rfc3339	string	RFC 3339 formatted time, e.g. "2026-03-27T12:00:00+03:00"
timezone	string	IANA timezone name, e.g. "Europe/Moscow"
utc_offset	int	UTC offset in seconds, e.g. 10800 for +03:00

Disk usage

Requires fs.enabled, path must be within fs.dirs.

AssemblyScript

import { diskUsage } from "@luminarys/sdk-as";

const du = diskUsage("/data");
// du.total_bytes, du.free_bytes, du.used_bytes, du.used_pct

Go

du, err := sdk.DiskUsage("/data")
fmt.Printf("Total: %d MB, Free: %d MB, Used: %.1f%%\n",
    du.TotalBytes/1024/1024, du.FreeBytes/1024/1024, du.UsedPct)

Rust

let du = disk_usage("/data")?;
println!("Total: {} MB, Free: {} MB, Used: {:.1}%",
    du.total_bytes / 1024 / 1024, du.free_bytes / 1024 / 1024, du.used_pct);

DiskUsageResult:

Field	Type	Description
total_bytes	int64	Total disk space in bytes
free_bytes	int64	Free disk space in bytes
used_bytes	int64	Used disk space in bytes
used_pct	float64	Usage percentage (0.0–100.0)

Environment variables

Reads values from the env section of the manifest — not from system environment.

AssemblyScript

import { getEnv } from "@luminarys/sdk-as";

const apiKey = getEnv("API_KEY");

Go

apiKey := sdk.GetEnv("API_KEY")

Rust

let api_key = get_env("API_KEY");

Values in the manifest env section support ${VAR} expansion from the system environment and .env files:

env:
  API_KEY: "${API_KEY}"                    # from system env or .env file
  DB_HOST: "postgres.internal"             # literal value
  TIMEOUT: "${TIMEOUT:-30}"               # default if unset
  SECRET: "${SECRET:?SECRET is required}"  # error if unset

Resolution order:

1. .env file in the working directory (loaded first, does not overwrite existing vars)
2. .env.local file in the working directory (loaded second, does not overwrite)
3. System environment variables
4. ${VAR:-default} fallback if variable is unset or empty

Supported syntax (same as docker-compose):

Syntax	Description
${VAR}	Value of VAR, empty if unset
${VAR:-default}	Value of VAR, or default if unset or empty
${VAR-default}	Value of VAR, or default if unset (empty counts as set)
${VAR:?error}	Value of VAR, or fatal error if unset or empty
${VAR?error}	Value of VAR, or fatal error if unset

Logging

Requires log.skill_log: true in host config. Logs are automatically tagged with the skill ID.

AssemblyScript

import { log, logInfo, logError, LogField } from "@luminarys/sdk-as";

// Simple message
logInfo("Processing started");

// With structured fields
const f1 = new LogField(); f1.name = "method"; f1.value = "process";
const f2 = new LogField(); f2.name = "items"; f2.value = "42";
log("info", "Processing request", [f1, f2]);

Go

// Simple message
sdk.LogInfo("Processing started", nil)

// With structured fields
sdk.Log("info", "Processing request", map[string]any{
    "method": "process",
    "items":  42,
})

Rust

// Simple message
log_info("Processing started", &[]);

// With structured fields
log_msg("info", "Processing request", &[("method", "process"), ("items", "42")]);

Log levels:

Level	When to use
debug	Debugging details (hidden by default)
info	Normal operation
warn	Unexpected situation, operation continues
error	Error, attention required