feat: add ClaudeCodeClient — LLM inference via Claude Code SDK (no API key)

[openbiocure]

Summary

Adds a new ClaudeCodeClient LLM provider that uses the Claude Agent SDK for inference. Authenticates via Claude Code's OAuth credentials (~/.claude) — no API key required.

Motivation

Users of Claude Code (CLI, desktop, IDE extensions) already have authenticated sessions. This client lets Graphiti piggyback on that auth instead of requiring a separate Anthropic API key. Useful for developers who want to use Graphiti locally without managing API keys.

How it works

• Spawns a persistent Claude Code subprocess via ClaudeSDKClient
• First call ~8s (subprocess startup), subsequent calls ~3s (warm)
• Monitors context usage via get_context_usage() — auto-recycles subprocess when context exceeds threshold (default 60%)
• Parses JSON from text responses (same pattern as GroqClient)
• Thread-safe via async lock

Usage

from graphiti_core.llm_client.claude_code_client import ClaudeCodeClient
from graphiti_core.llm_client.config import LLMConfig

client = ClaudeCodeClient(config=LLMConfig(model='haiku'))
graphiti = Graphiti(graph_driver=driver, llm_client=client, embedder=embedder)

Testing

Tested end-to-end with FalkorDB + HuggingFace sentence-transformers embeddings:

• Episode ingestion: ~13s (including subprocess startup)
• Search returns correctly extracted entities and relationships
• Context recycling works — subprocess restarts cleanly when context fills up

Notes

• Requires claude-agent-sdk (optional dependency, lazy import)
• Falls back gracefully — ClaudeCodeClient is None when SDK not installed
• Follows the same pattern as GroqClient — implements _generate_response, lets base class handle schema injection

[zep-cla-assistant]

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[openbiocure]

I have read the CLA Document and I hereby sign the CLA behalf on myself, e-mail: openbiocure@gmail.com