// src/config/logger.ts
import winston from 'winston';
const logLevel = process.env.LOG_LEVEL || 'info';
// In MCP (stdio) transports, stdout must be reserved strictly for JSON-RPC.
// I'm configuring the console transport to write ALL levels to stderr to avoid
// corrupting the JSON stream that Claude/Desktop reads from stdout.
const allLevels = Object.keys(winston.config.npm.levels);
export const logger = winston.createLogger({
level: logLevel,
format: winston.format.combine(
winston.format.timestamp(),
winston.format.errors({ stack: true }),
winston.format.json()
),
transports: [
new winston.transports.Console({
// Route every level to stderr; do not print to stdout
stderrLevels: allLevels as any,
// Keep output simple/plain (no ANSI color codes)
format: winston.format.combine(
winston.format.simple()
)
})
]
});
// Add file transport if log file is specified
if (process.env.LOG_FILE) {
logger.add(new winston.transports.File({
filename: process.env.LOG_FILE,
format: winston.format.json()
}));
}
