# Worker Configuration Options

The Hatchet worker can be configured via environment variables and programmatic options. This document contains a list of all available options.

## Basic Configuration

Variable, Description, Default Value

`HATCHET_CLIENT_TOKEN`, Authentication token for the worker
`HATCHET_CLIENT_HOST_PORT`, GRPC server host and port, \* Inherited from token
`HATCHET_CLIENT_API_URL` (TypeScript SDK), API server host and port, \* Inherited from token
`HATCHET_CLIENT_SERVER_URL` (Go SDK), API server host and port, \* Inherited from token
`HATCHET_CLIENT_NAMESPACE`, Namespace prefix for the worker, \* Inherited from token

## Worker Runtime Configuration

Variable, Description, Default Value

`name`, Friendly name of the worker
`slots`, Maximum number of concurrent runs, `100`
`durable_slots`, Maximum number of concurrent durable tasks, `1000`

## Worker healthcheck server (Python SDK)

These variables enable a local HTTP server that exposes `/health` and `/metrics` for a running worker.

Variable, Description, Default Value

`HATCHET_CLIENT_WORKER_HEALTHCHECK_ENABLED`, Enable the local worker healthcheck server, `false`
`HATCHET_CLIENT_WORKER_HEALTHCHECK_PORT`, Port for the local worker healthcheck server, `8001`
`HATCHET_CLIENT_WORKER_HEALTHCHECK_EVENT_LOOP_BLOCK_THRESHOLD_SECONDS`, If the worker listener process event loop is blocked longer than this threshold, `/health` returns 503, `5.0`

## TLS Configuration

Variable, Description, Default Value

`HATCHET_CLIENT_TLS_STRATEGY`, TLS strategy (tls, mtls, none), `tls`
`HATCHET_CLIENT_TLS_CERT_FILE`, Path to TLS certificate file
`HATCHET_CLIENT_TLS_KEY_FILE`, Path to TLS key file
`HATCHET_CLIENT_TLS_ROOT_CA_FILE`, Path to TLS root CA file
`HATCHET_CLIENT_TLS_SERVER_NAME`, TLS server name

## Logging Configuration

Variable, Description, Default Value

`HATCHET_CLIENT_LOG_LEVEL`, Log level for the worker client, `WARN`
`HATCHET_CLIENT_LOG_FORMAT`, Log format for the worker client, `console`
`HATCHET_CLIENT_GRPC_MAX_RECV_MESSAGE_LENGTH`, Maximum gRPC message receive size (Python SDK only), `4MB`
`HATCHET_CLIENT_GRPC_MAX_SEND_MESSAGE_LENGTH`, Maximum gRPC message send size (Python SDK only), `4MB`