Best for
- Developers on long-running projects using Claude Code, Cursor, Windsurf, or similar tools
- Teams needing cross-session memory and codebase understanding
C
ContextStream MCP Server
Official
Persistent memory and semantic code search for AI coding assistants
GitHub source repository ↗
73FMRS · B
A feature-rich memory and code-search MCP server with a setup wizard covering major editors and a free tier. Its core value is cross-session memory, semantic search, and compaction protection, at the cost of cloud dependency and an API key.
ContextStream MCP Server gives MCP-compatible AI coding assistants (Claude Code, Cursor, VS Code Copilot, Windsurf, and more) persistent memory, semantic code search, and cross-session learning. It indexes your codebase, records decisions and lessons, maps the dependency graph, and pulls in team knowledge from GitHub, Slack, and Notion. Per vendor benchmarks it scores 90.0% on the full 500-instance LongMemEval-S suite with the official GPT-4o judge.
Tools
init
Get workspace state and prepare context for every message
context
Deliver the right workspace context on every message
search
Code search with semantic, hybrid, keyword, pattern, exhaustive, and refactor modes
memory
Manage events, decisions, docs, runbooks, tasks, todos, diagrams, and transcripts
session
Capture decisions and lessons, recall past sessions and plans
qa
Grounded Q&A over your workspace knowledge base with citations
graph
Dependency mapping, impact analysis, circular-dependency and dead-code detection
capsule
Package portable, shareable context snapshots for agent handoffs
entity
Manage tickets, incidents, releases, sprints, OKRs, and risks
project
Project indexing, scope, and de-indexing management
workspace
Workspace management
skill
Reusable instruction and action bundles, portable across tools
media
Index and search images, video, audio, and documents
vcs
Repository links management
reminder
Reminders
integration
Third-party integrations
help
Diagnostics and version information
Setup
Run npx --prefer-online -y @contextstream/mcp-server@latest setup to auto-configure editors, or manually add the npx launch command to your MCP config with CONTEXTSTREAM_API_KEY (required) and CONTEXTSTREAM_API_URL (optional, default https://api.contextstream.io). A hosted remote endpoint at https://mcp.contextstream.io/mcp (streamable-http, with OAuth) is also available.
claude_desktop_config.json
{"mcpServers":{"contextstream":{"command":"npx","args":["--prefer-online","-y","@contextstream/mcp-server@latest"],"env":{"CONTEXTSTREAM_API_URL":"https://api.contextstream.io","CONTEXTSTREAM_API_KEY":"your_key"}}}}
Fit and risk
Not for
- Users unwilling to index code to a cloud service
- One-off scripts that need no persistent context
Required permissions
- Requires a ContextStream API key (secret env var)
- Reads and indexes project code files
- Optionally connects GitHub, Slack, and Notion integrations
- Writes MCP configs, rules, and lifecycle hooks into editor settings
Risks and side effects
- Indexed code is stored in ContextStream's cloud (vendor states isolation per workspace)
- A leaked API key could expose workspace data
- Breaking changes with @modelcontextprotocol/sdk 1.28.0+
- Hosted HTTP OAuth may be blocked on corporate networks
Troubleshooting
- Run contextstream-mcp doctor to check auth, index health, rules, and hooks
- Verify CONTEXTSTREAM_API_URL and CONTEXTSTREAM_API_KEY are set
- Remove stale version pins like @contextstream/[email protected]
- Restart the editor after config changes
- Use stdio with an API key if OAuth is blocked
- Check SDK resolution for Zod schema errors
Use cases
Remember decisions, plans, and lessons across sessions
Semantic search over large codebases
Pre-compaction capture of critical state before context loss
Team knowledge integration with cited Q&A
Context handoff between agents
Supported clients
Claude CodeFull support
CursorFull support
WindsurfFull support
ClineFull support
Roo CodeFull support
VS Code + GitHub CopilotPartial support
Kilo CodePartial support
Codex CLIPartial support
OpenCodePartial support
AiderPartial support
AntigravityPartial support
Claude DesktopPartial support