Solitaire: Open-Source Identity Layer for AI Agents Built with Claude Code
Solitaire is an open-source project that provides an identity layer for AI agents, built primarily using Claude Code as the development environment. Unlike agent memory tools that focus on recall, Solitaire addresses how agents work with users over time, aiming to move beyond what the creator describes as "a smart stranger with a better notebook."
Key Features and Architecture
The system has been in production since February, with the current version shaped by 600+ sessions and 15,700+ entries in real use. Key architectural decisions emerged from observing failure modes and fixing actual problems:
- MCP server architecture and hook system designed around how Claude Code handles tool calls and session state
- Retrieval weighting that adjusts based on what actually proved useful in practice
- Boot structure and persona compilation refined through production use
- Self-correcting knowledge graph with contradiction detection, confidence rescoring, and entity relinking
- Tiered boot context so agents arrive briefed rather than blank
Identity and Behavior System
Solitaire's identity system evolves through actual interaction rather than static configuration:
- Disposition traits (warmth, assertiveness, conviction, observance) compile from interaction patterns and evolve across sessions
- Persona and behavioral identity develops from real use, not config file editing
- Session residues carry forward how work felt, not just what was discussed
- New users get guided onboarding that builds the partner through conversation - pick a name, describe needs, and the system assembles persona from answers (no YAML required)
Local-First Design
The local-first approach is non-negotiable in the design:
- All storage is SQLite + JSONL in your workspace directory
- Zero network requests from the core engine
- No cloud dependency, no telemetry, no external API calls for memory operations
- Automatic rolling backups with no setup required
- Your data stays on your machine
Installation and Compatibility
Install via pip install solitaire-ai (note: not install solitaire, which is an unrelated package). The project is built for Claude Code first but supports other agent platforms. It's memory-agnostic - works with existing memory layers or provides one if needed.
License and Availability
Free and open source under AGPL-3.0, with commercial licensing available for proprietary embedding. Available on PyPI and the MCP Registry. Two research papers from the longitudinal work are currently in review.
📖 Read the full source: r/ClaudeAI
👀 See Also
Hollow AgentOS Reduces Claude Code Token Usage by 68.5% with JSON-Native OS Approach
Hollow AgentOS, a JSON-native operating system layer for AI agents, reduces Claude Code token usage by 68.5% by eliminating wasteful shell command overhead. The tool plugs into Claude Code via MCP and runs local inference through Ollama.
Custom status line for Claude Code shows context usage, rate limits, and token counts at a glance
A custom script adds a persistent status line to Claude Code, displaying context %, 5-hour rate limit %, KV cache reads, cumulative input/output tokens, model name, and working directory — color-coded for dark terminals.
Developer Builds Power Automate MCP Server with 108 Tools, Cross-Platform Support
A developer built a Power Automate MCP server that expanded from 12 to 108 tools, covering Dataverse CRUD via OData, SharePoint management via Graph, Power Apps versioning, environment administration, and cross-platform support for Windows, macOS, and Linux.
OpenGauge: Open-source tool for tracking LLM agent costs locally
OpenGauge is an open-source tool that monitors API calls from LLM agents like OpenClaw, logging token usage, costs, and latency to a local SQLite database. It includes proxy mode for automatic logging, detailed cost statistics, and circuit breaker functionality to prevent runaway loops.