A Complete Guide to Integrating Claude API in Clawdbot (Taking Claude Sonnet 4.5 as an Example)

Clawdbot is an open-source personal AI assistant framework. Its core design relies heavily on Anthropic's Claude models, particularly their powerful tool use (function calling) and agentic reasoning capabilities. The most recommended and stable way to use it is by directly connecting the Anthropic Claude API (or compatible proxy services).

Based on the latest practices in early 2026, this article focuses on how to integrate the Claude API into Clawdbot, covering official Anthropic access and third-party proxies (such as defapi.org, which offers 50% cost savings for claude-sonnet-4.5), while providing configuration comparisons and key considerations.

1. Clawdbot's Native Support for Claude API

Clawdbot's underlying communication protocol is almost entirely based on Anthropic's Messages API (rather than the OpenAI format), which means:

Filling in Anthropic's base_url + api_key usually results in zero-cost compatibility.
tool use, tool_choice, and parallel tool calls have the best native support.
System prompts, XML tag-based chain-of-thought, and long context handling are perfectly aligned with Claude.

Therefore, Claude is the "First-Class Citizen" model of Clawdbot. Other models (Gemini, GPT, DeepSeek, etc.) require varying degrees of format conversion or proxy layers.

2. Comparison of the Two Main Integration Methods

Integration Method	Base URL	Model ID Example	Pros	Cons/Notes	Recommended Scenario
Official Anthropic API	`https://api.anthropic.com/v1`	`claude-4-sonnet-2025xxxx` or `claude-sonnet-4.5`	Lowest latency, full feature set, official direct connection	Requires Claude Pro/Max subscription or API credits; expensive	For users seeking ultimate stability and tool performance
defapi.org Proxy	`https://api.defapi.org/api/v1`	`anthropic/claude-sonnet-4.5`	50% cost savings vs official, OpenAI-style interface, supports multimodal	Non-official, occasional compatibility tweaks needed, tool support needs testing	Limited budget / desiring unified interface format

(defapi.org is a multi-model unified proxy platform that wraps Claude into an OpenAI-like /chat/completions interface while retaining most of Claude's native capabilities.)

3. Steps: Using official Anthropic Claude API (Recommended Choice)

Get Anthropic API Key
Log in to https://console.anthropic.com → API Keys → Create Key.
Copy the key starting with sk-ant-.
Run Clawdbot onboarding (if not yet installed)

npx clawdbot@latest onboard

Or modify the configuration directly if already installed.

Modify Environment Variables or Config File

Most users use a .env file (located in the Clawdbot root directory):

# Required
PROVIDER=anthropic
ANTHROPIC_API_KEY=sk-ant-api03-your-real-key-xxx

# Optional - Specify model (defaults to latest Sonnet if empty)
DEFAULT_MODEL=claude-sonnet-4.5
# Or a more specific version (recommended)
# DEFAULT_MODEL=claude-4-sonnet-2025xxxx

# If you have a custom Anthropic address (Enterprise/Self-hosted scenarios)
# ANTHROPIC_BASE_URL=https://api.anthropic.com (This is the default)

# Other common tuning (Optional)
MAX_TOKENS=8192
TEMPERATURE=0.3          # Claude recommends 0~0.5 for stable agent behavior
TOP_P=0.95

Restart Clawdbot Service

# If running via docker / pm2
clawdbot restart
# Or directly via npx
npx clawdbot start

Verify Success

In the Telegram/WhatsApp/Web interface, send:

"Please call a tool to get the current time in Beijing."

If Clawdbot correctly invokes the time tool and replies, the Claude API is successfully integrated.

4. Using defapi.org to Access Claude Sonnet 4.5 (Cost-Effective Solution)

If official credits are insufficient or you want high cost-efficiency (50% cheaper), you can use defapi:

Register at https://defapi.org and get an API Key (supports Alipay, etc.).
Configure .env:

# Switch to openai compatible mode (defapi uses /chat/completions)
PROVIDER=openai
OPENAI_API_KEY=def-your-defapi-key
OPENAI_BASE_URL=https://api.defapi.org/api

# Important: Must use the full prefix for the model
DEFAULT_MODEL=anthropic/claude-sonnet-4.5

# Suggested additional settings (Claude-style parameters will be passed through)
TEMPERATURE=0.4
MAX_TOKENS=16384          # defapi supports long context

Extra Compatibility Adjustment (If tool calls fail)

Add this line to Clawdbot's config or prompt template:

tool_choice: "auto"   # or "required" depending on the scenario

Some proxies do not perfectly support parallel tool calls. You can temporarily lower Clawdbot's parallel tool count (config → max_parallel_tools: 2).

5. FAQ & Best Practices

Error "tool_use not supported" or Format Incompatibility
→ 99% of the time, this is caused by using a non-native Claude interface without proper format conversion. This rarely happens when using official Anthropic or the Claude models on defapi.
Context Exceedance & Frequent Truncation
→ Set MAX_TOKENS higher (Claude 4 series generally supports 128k~200k) and emphasize "prioritize summarizing history" in the system prompt.
Wanting to use both Claude 4 Opus + Sonnet 4.5 simultaneously
Clawdbot supports sub-agents / multi-model layering. The simplest way is to write a skill that routes complex tasks to Opus while using Sonnet for daily tasks.
Cost Monitoring
It is strongly recommended to enable usage email alerts in the Anthropic Console or defapi dashboard. Agentic behavior in Clawdbot can easily burn through hundreds of dollars in a single night if left in a loop.