Configuration

This page covers all configuration options for Anvil.

Environment Variables

LLM Provider Keys

Variable	Provider	Description
`ANTHROPIC_API_KEY`	Anthropic	Claude API key
`OPENAI_API_KEY`	OpenAI	GPT-4 API key
`XAI_API_KEY`	xAI	Grok API key

Optional Keys

Variable	Description
`FIRECRAWL_API_KEY`	For fetching API documentation

Setting Variables

# In terminal
export ANTHROPIC_API_KEY="sk-ant-..."

# In .env file
ANTHROPIC_API_KEY=sk-ant-...
FIRECRAWL_API_KEY=fc-...

Anvil Constructor Options

Basic Options

from anvil import Anvil

anvil = Anvil(
    # LLM Provider
    provider="anthropic",           # "anthropic", "openai", "grok"
    model=None,                     # Provider-specific default if None
    api_key=None,                   # From environment if None

    # Tool Storage
    tools_dir="./anvil_tools",      # Where to save generated tools
)

Self-Healing Options

anvil = Anvil(
    self_healing=True,              # Enable automatic regeneration
    max_heal_attempts=2,            # Max retries before giving up
)

Generator Mode

anvil = Anvil(
    mode="local",                   # "local", "stub", or "cloud"
    use_stub=False,                 # Shorthand for mode="stub"
)

Mode	Description
`local`	Use LLM to generate tools (default)
`stub`	Generate placeholder tools (no LLM)
`cloud`	Use Anvil Cloud (coming soon)

Credential Options

anvil = Anvil(
    interactive_credentials=True,   # Prompt for missing keys
    env_file=".env",                # Where to save credentials
)

Security Options

from anvil.sandbox import SecurityPolicy

anvil = Anvil(
    verified_mode=True,             # Verify code in sandbox
    security_policy=SecurityPolicy( # Custom policy
        allow_network=True,
        allow_subprocess=False,
    ),
)

Logging Options

anvil = Anvil(
    log_file="./anvil.log",         # Enable file logging
)

SecurityPolicy Options

from anvil.sandbox import SecurityPolicy

policy = SecurityPolicy(
    # Network
    allow_network=False,
    allowed_hosts=None,             # ["api.example.com"]

    # Filesystem
    allow_filesystem_read=True,
    allow_filesystem_write=False,
    allowed_paths=None,             # ["/tmp", "./data"]

    # System
    allow_subprocess=False,
    allow_env_access=True,

    # Resource Limits
    max_memory_mb=256,
    max_cpu_seconds=30.0,
    max_output_size_kb=1024,

    # Custom Blocks
    blocked_imports=None,           # Additional imports to block
    blocked_functions=None,         # Additional functions to block
)

InputParam Options

from anvil import InputParam

param = InputParam(
    name="query",                   # Parameter name
    param_type="str",               # "str", "int", "float", "bool", "list"
    required=True,                  # Is this required?
    description="Search query",     # Help text
    default=None,                   # Default value
)

Default Models

When model=None, these defaults are used:

Provider	Default Model
Anthropic	`claude-sonnet-4-20250514`
OpenAI	`gpt-4o`
Grok	`grok-2-latest`

File Structure

After initialization, your project structure:

my-project/
├── .env                      # API keys (gitignored)
├── .gitignore                # Protects .env
├── anvil_tools/
│   ├── __init__.py
│   ├── tool_registry.json    # Tool metadata
│   ├── search_github.py      # Generated tool
│   └── get_weather.py        # Generated tool
├── anvil.log                 # Event log (if enabled)
└── main.py                   # Your code

Tool Registry Format

anvil_tools/tool_registry.json:

{
  "search_github": {
    "name": "search_github",
    "intent": "Search GitHub repositories",
    "docs_url": "https://docs.github.com/...",
    "hash": "a1b2c3d4e5f6",
    "version": "1.0",
    "status": "active",
    "created_at": "2025-01-18T10:00:00Z",
    "last_generated": "2025-01-18T10:00:00Z",
    "error_count": 0
  }
}

Generated Tool Format

anvil_tools/search_github.py:

# ---
# ANVIL-MANAGED: true
# INTENT-HASH: a1b2c3d4e5f6
# ---

import requests

def run(query: str, **kwargs) -> dict:
    """Search GitHub repositories."""
    response = requests.get(
        "https://api.github.com/search/repositories",
        params={"q": query}
    )
    response.raise_for_status()
    return response.json()

Log File Format

JSON Lines format (one JSON object per line):

{"timestamp": "2025-01-18T10:00:00Z", "event_type": "tool_generated", "tool_name": "search_github", "duration_ms": 1250.5, "metadata": {}}
{"timestamp": "2025-01-18T10:00:01Z", "event_type": "tool_executed", "tool_name": "search_github", "duration_ms": 150.2, "metadata": {}}

Recommended Configurations

Development

anvil = Anvil(
    tools_dir="./anvil_tools",
    self_healing=True,
    interactive_credentials=True,
)

Testing

anvil = Anvil(
    use_stub=True,                  # No LLM calls
    self_healing=False,
)

Production

anvil = Anvil(
    tools_dir="/app/tools",
    self_healing=True,
    max_heal_attempts=1,
    verified_mode=True,
    interactive_credentials=False,
    log_file="/var/log/anvil/anvil.log",
)

CI/CD

anvil = Anvil(
    use_stub=True,
    interactive_credentials=False,
)