DeepSeek-Reasonix Configuration Resolution Order: Flags, Project, User, and Defaults

DeepSeek-Reasonix resolves configuration values through a strict four-step cascade: command-line flags override project-level settings in ./reasonix.toml, which in turn override user-level settings in ~/.reasonix/config.toml, finally falling back to built-in binary defaults.

DeepSeek-Reasonix is an open-source AI reasoning engine that determines its runtime behavior through a hierarchical configuration system. Understanding the configuration resolution order is essential for managing model selections, language preferences, and execution parameters across different environments. The resolution cascade is explicitly documented in the source code within internal/config/config.go and ensures predictable behavior whether you are running a one-off command or managing multi-project workflows.

Configuration Resolution Cascade in DeepSeek-Reasonix

The resolution order follows a four-step priority chain: Flags → Project → User → Defaults. When the engine starts, it queries each source in sequence, with higher-priority values overwriting lower-priority ones. This cascade allows temporary overrides via CLI flags while maintaining persistent defaults at the project or user level.

According to the package header in internal/config/config.go, the resolution order is explicitly defined as flags taking precedence over project files, project files over user files, and user files over compiled defaults. The same hierarchy is restated in internal/config/render.go when displaying the rendered configuration to users.

The Four Levels of Configuration Priority

Command-Line Flags (Highest Priority)

Command-line flags provide immediate, ephemeral control over runtime parameters. Values passed directly on the CLI—such as --model, --max-steps, or --local—take precedence over all other configuration sources.

# Override all other config sources with a specific model

reasonix chat --model deepseek-coder

Flags are useful for testing different models without modifying persistent configuration files or for scripting one-off tasks with specific parameters.

Project-Level Configuration (./reasonix.toml)

The project-level file resides in the current working directory as ./reasonix.toml. This file allows repositories to define their own defaults, such as specifying a particular provider or model for that specific codebase.

# ./reasonix.toml - placed in the repository root

default_model = "deepseek-chat"
language = "en"

When you run reasonix chat within that directory, the engine selects deepseek-chat unless you provide a different --model flag. This level is ideal for team consistency, ensuring everyone working on the repository uses the same base configuration.

User-Level Configuration (~/.reasonix/config.toml)

The user-level file stores global preferences that apply across all projects unless overridden. On Unix systems, this is located at ~/.reasonix/config.toml; on Windows, it resides at %APPDATA%\reasonix\config.toml.

# ~/.reasonix/config.toml - global user settings

default_model = "gpt-4"
language = "auto"

This level is perfect for setting environment-wide preferences like default language settings or credential store locations that should persist across different projects.

Built-In Defaults (Fallback)

Built-in defaults are hard-coded values compiled directly into the binary. These serve as the final safety net, ensuring DeepSeek-Reasonix can start even when no configuration files exist. Typical fallbacks include default_model = "gpt-4" and language = "auto".

Inspecting the Effective Configuration

To verify which configuration sources are active and debug the resolution order, use the built-in config inspection command:

# Display the final resolved configuration with source attribution

reasonix config show

The output lists each field alongside its source—flag, project, user, or default—confirming exactly which level supplied each value. This functionality is implemented in internal/config/render.go, which reiterates the resolution order when displaying the rendered configuration.

Key Source Files and Implementation

The resolution logic is centralized in specific files within the repository:

• internal/config/config.go: Contains the core configuration struct and the package-level comment documenting the resolution order (Flags → Project → User → Defaults).
• internal/config/render.go: Implements the helper that prints resolved configurations, restating the cascade order at line 48.
• reasonix.example.toml: Provides a documented example of project-level configuration, explicitly referencing the resolution hierarchy in its header comments.

These files demonstrate how DeepSeek-Reasonix maintains predictable configuration behavior across different deployment scenarios.

Summary

• Command-line flags override all other sources, providing temporary, per-run control.
• Project files (./reasonix.toml) supply repository-specific defaults while allowing flag overrides.
• User files (~/.reasonix/config.toml) set global preferences across all projects.
• Built-in defaults ensure the application runs without any external configuration.

Frequently Asked Questions

What is the exact configuration resolution order in DeepSeek-Reasonix?

DeepSeek-Reasonix follows a strict four-step hierarchy: command-line flags take precedence over project-level settings in ./reasonix.toml, which override user-level settings in ~/.reasonix/config.toml, with built-in binary defaults serving as the final fallback. This order is explicitly documented in internal/config/config.go and ensures predictable behavior across different environments.

How do I temporarily override a project configuration without editing files?

Use command-line flags to temporarily override any setting. For example, running reasonix chat --model gpt-4 will use the GPT-4 model for that specific execution regardless of what is specified in ./reasonix.toml or your user configuration. Flags always take highest precedence in the resolution cascade.

Where should I store my personal API keys and global preferences?

Store personal API keys and global preferences in the user-level configuration file located at ~/.reasonix/config.toml on Unix systems or %APPDATA%\reasonix\config.toml on Windows. This keeps sensitive credentials out of project repositories while applying them across all your Reasonix sessions unless overridden by project settings or flags.

How can I verify which configuration source is being used for a specific setting?

Run reasonix config show to display the fully resolved configuration. The output indicates the source of each value—whether it came from a flag, project file, user file, or default—allowing you to verify the resolution order is working as expected. This command is implemented in internal/config/render.go.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}