Configuration

Marvin reads settings from environment variables and a .env file in the current directory. Environment variables take precedence. Set them before importing Marvin.

export MARVIN_AGENT_MODEL="openai:gpt-4o-mini"
export MARVIN_HOME_PATH="/path/to/marvin-data"
export MARVIN_ENABLE_DEFAULT_PRINT_HANDLER=false

Provider credentials such as OPENAI_API_KEY must be available to the provider SDK. Marvin’s settings loader reads its own fields from .env; it does not export unrelated .env entries into the process environment.

Storage

MARVIN_HOME_PATH defaults to ~/.marvin. Thread history uses a SQLite database there unless you set MARVIN_DATABASE_URL.

export MARVIN_DATABASE_URL="sqlite+aiosqlite:////absolute/path/to/history.db"

Database URLs must use an async driver. Vector memory is configured separately through its provider; MARVIN_MEMORY_PROVIDER defaults to chroma-ephemeral. The persistent Chroma provider string is chroma-db.

Output and limits

Setting	Purpose
`MARVIN_LOG_LEVEL`	Logging level, such as `INFO` or `DEBUG`
`MARVIN_LOG_EVENTS`	Log runtime events at debug level
`MARVIN_ENABLE_DEFAULT_PRINT_HANDLER`	Show agent activity on the console
`MARVIN_MAX_AGENT_TURNS`	Turn limit for an orchestrator run

MARVIN_AGENT_RETRIES is exposed in settings but is not currently passed to the model agent; changing it does not configure validation retries. See the settings API for the complete set of fields and defaults.

Runtime changes

import marvin

marvin.settings.enable_default_print_handler = False
marvin.defaults.model = "openai:gpt-4o-mini"

Model and memory defaults are initialized from settings during import. Change marvin.defaults when changing those defaults at runtime. Use model configuration for agent-specific models and temporary overrides.

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Storage

Output and limits

Runtime changes

​Storage

​Output and limits

​Runtime changes

Storage

Output and limits

Runtime changes