Local Brain

Local Brain

Chat with local Ollama models that have tools to explore your codebase.

Installation

Install local-brain:

uv pip install local-brain

Or with pipx:

pipx install local-brain

Requirements:

• Ollama running locally (https://ollama.ai)
• A model pulled (e.g., ollama pull qwen3)

Usage

local-brain "prompt"                    # Ask anything (auto-selects best model)
local-brain -v "prompt"                 # Show tool calls
local-brain -m qwen2.5:3b "prompt"        # Specific model
local-brain --trace "prompt"            # Enable OTEL tracing
local-brain --list-models               # Show available models
local-brain --root /path/to/project "prompt"  # Set project root
local-brain doctor                      # Check system health

Health Check

Verify your setup is working correctly:

local-brain doctor

This checks:

• Ollama is installed and running
• Recommended models are available
• Tools execute correctly
• Optional tracing dependencies

Example output:

🔍 Local Brain Health Check

Checking Ollama...
  ✅ Ollama is installed (ollama version is 0.13.1)

Checking Ollama server...
  ✅ Ollama server is running (9 models)

Checking recommended models...
  ✅ Recommended models installed: qwen3:latest

Checking tools...
  ✅ Tools working (9 tools available)

Checking optional features...
  ✅ OTEL tracing available (--trace flag)

========================================
✅ All checks passed! Local Brain is ready.

Examples

local-brain "What's in this repo?"
local-brain "Review the git changes"
local-brain "Generate a commit message"
local-brain "Explain how src/main.py works"
local-brain "Find all TODO comments"
local-brain "What functions are defined in utils.py?"
local-brain "Search for 'validate' in the auth module"

Model Discovery

Local Brain automatically detects installed Ollama models and selects the best one for tool-calling tasks:

# See what models are available
local-brain --list-models

Recommended models (verified tool support):

• qwen3:latest - General purpose, default choice (Tier 1)
• qwen2.5:3b - Resource-constrained environments (Tier 1)

Avoid these models (broken or unreliable tool calling):

• qwen2.5-coder:* - Broken with Smolagents
• llama3.2:1b - Hallucinations
• deepseek-r1:* - No tool support

If no model is specified, Local Brain auto-selects the best installed model.

Observability

Enable OpenTelemetry tracing with the --trace flag:

local-brain --trace "What files are here?"

This traces:

• Agent execution steps
• LLM calls with token counts
• Tool invocations with inputs/outputs

Install tracing dependencies:

pip install local-brain[tracing]

Security

All file operations are restricted to the project root (path jailing):

• Files outside the project directory cannot be read
• Shell commands execute within the project root
• Sensitive files (.env, .pem, SSH keys) are blocked
• Only read-only shell commands are allowed
• All tool outputs are truncated (200 lines / 20K chars max)
• Tool calls have timeouts (30 seconds default)

Available Tools

The model assumes these tools are available and uses them directly:

File Tools

• read_file(path) - Read file contents at a given path. Large files are truncated (200 lines / 20K chars). Has 30s timeout. Restricted to project root.
• list_directory(path, pattern) - List files in path matching a glob pattern (e.g., *.py, src/**/*.js). Excludes hidden files and common ignored directories. Returns up to 100 files. Has 30s timeout.
• file_info(path) - Get file metadata (size, type, modified time) for a given path. Has 30s timeout.

Code Navigation Tools (New in v0.6.0)

• search_code(pattern, file_path, ignore_case) - AST-aware code search. Unlike simple grep, shows intelligent context around matches (function/class boundaries). Supports Python, JavaScript, TypeScript, Go, Rust, Ruby, Java, C/C++.
• list_definitions(file_path) - Extract class/function definitions from a source file. Shows signatures and docstrings without full implementation code. Great for understanding file structure quickly.

Git Tools

• git_diff(staged, file_path) - Show code changes. Use staged=True for staged changes. Optionally provide a file_path. Output is truncated.
• git_status() - Check repo status. Output is truncated.
• git_changed_files(staged, include_untracked) - List changed files. Use staged=True for staged files, include_untracked=True to include untracked files. Output is truncated.
• git_log(count) - View commit history. count specifies number of commits (max 50). Output is truncated.

All tools return human-readable output or error messages on failure.