
ContextForge gives Claude, Cursor, and GitHub Copilot persistent memory across sessions through a hosted API. Install the npm package, drop your API key into your editor's MCP config, then run init to generate the right instruction files. Your AI can save architecture decisions, query past context semantically, track issues, and sync GitHub commits and PRs automatically. Everything lives in spaces and projects you can share with your team. The MCP exposes 30+ tools for ingesting knowledge, searching memory, managing tasks, and exporting snapshots, but you mostly just talk naturally and let the AI pick the right calls. Free tier available, no local database required.
Give Claude Code, Cursor, and GitHub Copilot persistent memory across sessions via the Model Context Protocol (MCP). Stop re-explaining your project every time.
ContextForge MCP is an open-source MCP server that connects your AI coding assistants to long-term, searchable memory. Decisions, architecture notes, debugging context, and project knowledge stay available across every session — across every tool that supports MCP.
[!NOTE] Works automatically, no config needed (v0.5.1+). On connect, the server sends startup instructions to your AI client. Clients that honor them (Claude Desktop, Claude Code) load your project memory at the start of every session and save new decisions proactively — without you editing any settings. Running
init(Step 4) is now a reinforcement, not a requirement, and still helps on clients that don't yet honor server instructions (e.g. Cursor).
No install step needed — the setup below runs the server via npx -y contextforge-mcp, which fetches it on demand and keeps it up to date.
Prefer a global install for slightly faster cold starts?
npm install -g contextforge-mcpis optional; if you do it, you can drop thenpx -yprefix from the commands below.
cf_)Edit ~/Library/Application Support/Claude/claude_desktop_config.json:
{
"mcpServers": {
"contextforge": {
"command": "npx",
"args": ["-y", "contextforge-mcp"],
"env": {
"CONTEXTFORGE_API_KEY": "your-api-key-here"
}
}
}
}
Restart Claude Desktop.
claude mcp add contextforge -s user \
-e CONTEXTFORGE_API_KEY=your-api-key-here \
-- npx -y contextforge-mcp
Restart Claude Code and run /mcp to verify it's connected.
Add to your Cursor MCP settings:
{
"mcpServers": {
"contextforge": {
"command": "npx",
"args": ["-y", "contextforge-mcp"],
"env": {
"CONTEXTFORGE_API_KEY": "your-api-key-here"
}
}
}
}
Add to your Copilot MCP config:
{
"servers": {
"contextforge": {
"command": "npx",
"args": ["-y", "contextforge-mcp"],
"env": {
"CONTEXTFORGE_API_KEY": "your-api-key-here"
}
}
}
}
With v0.5.1+ the server auto-loads memory on supporting clients (see the note at the top), so this step is optional but recommended: it reinforces the behavior, covers clients that don't honor server instructions, and fully overrides the built-in file-based memory.
Set up your project so your AI editor always prefers ContextForge memory:
npx contextforge-mcp init
By default, init auto-detects which editor your project uses and writes three rule sections and two hooks:
SessionStart hook with matcher compact in .claude/settings.json. When Claude Code compacts a long conversation, the hook runs npx -y contextforge-mcp recall and re-injects the session objective, memories relevant to what you are working on, your project's 10 most recent memories and pending tasks, so decisions saved in ContextForge survive the summary.UserPromptSubmit hook that runs the generated script .claude/hooks/contextforge-objective.cjs with plain node (~50 ms). It records your prompts to ~/.contextforge-mcp/sessions/<session_id>.jsonl on your machine, so recall can put the session's objective back after a compaction. The log is pruned after 14 days and never uploaded; see the privacy note below for what recall sends.Files written:
CLAUDE.md for Claude Code (signals: existing CLAUDE.md or .claude/ directory).cursorrules for Cursor (signals: existing .cursorrules or .cursor/ directory).claude/settings.json for Claude Code — merged, never overwritten; only the two ContextForge hook groups are added.claude/hooks/contextforge-objective.cjs for Claude Code — the generated objective hook script (safe to commit; refreshed by init when a new version ships; Claude Code's own system turns — prompts that start with an XML-like tag and contain a closing tag — are not logged)If no editor is detected, both files are generated.
On clients that honor server instructions (Claude Desktop, Claude Code), ContextForge is used automatically even without this step. On other clients — or to guarantee the built-in file-based auto-memory never wins — run init: it writes explicit rules that always route memory to ContextForge.
--editor| Flag | Behavior |
|---|---|
--editor=claude | Generate only CLAUDE.md |
--editor=cursor | Generate only .cursorrules |
--editor=all | Generate both, skip detection |
Re-running init is idempotent per section — sections you already have are left untouched; missing ones are appended. Upgrading from an older version? Just re-run npx contextforge-mcp init: it adds the new Startup Context section without touching the rest of your file.
npx contextforge-mcp --version # also: -v, version
Prints the installed version (e.g. contextforge-mcp 0.5.2).
Long sessions get compacted: Claude Code summarizes the conversation to free space, and the summary keeps the gist but drops details — usually the decisions, and often the task itself. init installs two hooks that fix both:
UserPromptSubmit) — records each prompt locally so the session's first real request is never lost to the summary.SessionStart, matcher compact) — fires right after every compaction and prints back, in this order: the session objective and the latest request before the cut; up to 5 memories relevant to the current work (semantic search over the objective, git branch, recent commit subjects and changed files, whatever their age); the project's 10 most recent memories; up to 5 pending tasks; and a reminder to call memory_query for anything older. The whole block stays around 4 KB and is injected once, never pinned, so it does not move the compaction trigger.The relevance search is one metered query per compaction. It only runs when there is a session objective or you are on a non-default branch (git-only context on main is noise), it runs in parallel with the other fetches under the same 6-second stage deadline, so a slow search can never drop the rest of the block, and CONTEXTFORGE_RECALL_RELEVANCE=0 in the environment turns it off entirely.
The hooks run as plain shell commands, so recall reads your API key from CONTEXTFORGE_API_KEY if set, otherwise from the contextforge server entry in ~/.claude.json (where claude mcp add stores it), otherwise from a project .mcp.json. It needs a linked project (.contextforge in the repo root). If anything is missing it prints nothing and never blocks the session. Note that a CONTEXTFORGE_API_KEY exported in your shell profile wins over ~/.claude.json: if it holds an old key, recall silently prints nothing.
Try it by hand from your project directory:
npx contextforge-mcp recall # prints the block for the newest session in this directory
npx contextforge-mcp recall --stats # local numbers: recalls, objective coverage, follow-up queries
Privacy: the prompt log and the recall stats live under ~/.contextforge-mcp/ on your machine and are never uploaded. What leaves the machine: after a compaction, recall sends the session objective (at most 600 characters, together with the git branch, recent commit subjects and changed file names) to ContextForge as the search query, the same way memory_query sends a query; it is not stored. Note that .claude/settings.json is usually committed, so teammates who pull the repo get the prompt hook too; they can remove the UserPromptSubmit group to opt out.
Nothing to reconfigure. Update to the latest and restart your AI client:
npm update -g contextforge-mcp # only if you installed globally; npx users get it on next launch
You do not need to re-run init for the auto-load behavior. To get the post-compaction recall hook and the session objective hook, run npx contextforge-mcp init once in each project; it only adds what is missing. Since 0.13.2 the server reminds you once per project when the recall hook is installed but the objective hook is missing or outdated.
ContextForge defines 69 tools across Knowledge Management, GitHub Integration, Issue Tracking, and Collaboration. No capability was ever removed — every tool below is fully callable — but as of v0.11.0, your AI client sees only 11 of them by default (CONTEXTFORGE_TOOLS=lean, the default):
memory_query, memory_ingest, memory_check_freshness, memory_confirm, memory_correct, memory_forget, tasks_list, tasks_what_next, session_list, memory_help.cf_tools — one gateway tool that discovers and runs the other 59. Ask your AI naturally ("sync my git commits", "restore from a snapshot", "olvida ese recuerdo viejo") and it searches (English or Spanish) and calls the right tool for you — no need to know an exact name.Set CONTEXTFORGE_TOOLS=full to expose all 69 tools directly to your client instead, matching the behavior of versions before 0.11.0. See Environment Variables.
Why lean by default: 69 tool schemas cost ~15,000 tokens of context on every session, push past Cursor's 40-tool cap, and contribute to the accuracy degradation several clients show past ~50 tools. The lean set cuts that to ~3,500 tokens (~77% less) while keeping every tool one call away via cf_tools.
| Tool | Description |
|---|---|
memory_ingest | Save knowledge to memory |
memory_query | Search your knowledge semantically |
memory_list_items | List all stored items |
memory_delete | Remove specific items |
memory_ingest_batch | Save multiple items at once |
memory_delete_batch | Delete items by filter |
| Tool | Description |
|---|---|
memory_list_spaces | List your spaces |
memory_create_space | Create a new space |
memory_delete_space | Delete a space |
memory_move_space | Move space to project |
memory_list_projects | List your projects |
memory_create_project | Create a new project |
memory_delete_project | Delete a project |
memory_link_project | Link directory to project |
memory_unlink_project | Unlink directory |
memory_current_project | Show linked project |
| Tool | Description |
|---|---|
memory_git_connect | Connect a GitHub repo |
memory_git_list | List connected repos |
memory_git_activate | Activate/deactivate webhook |
memory_git_sync | Import existing history |
memory_git_commits | List synced commits |
memory_git_prs | List synced PRs |
memory_git_disconnect | Disconnect a repo |
| Tool | Description |
|---|---|
issues_list | List your issues |
issues_create | Create a new issue |
issues_start | Mark as in progress |
issues_resolve | Mark as resolved |
issues_resolve_by_name | Resolve by title |
issues_assign | Assign to collaborator |
issues_what_next | Get recommendation |
| Tool | Description |
|---|---|
project_share | Share project by email |
collaborators_list | List collaborators |
| Tool | Description |
|---|---|
memory_snapshot_create | Create a backup |
memory_snapshot_list | List all snapshots |
memory_snapshot_restore | Restore from backup |
memory_snapshot_delete | Delete a snapshot |
memory_export | Export to JSON/MD/CSV |
memory_import | Import from file |
| Tool | Description |
|---|---|
memory_stats | View usage statistics |
memory_relate | Link two items |
memory_help | Show help |
Running several Claude Code sessions in parallel (worktrees, agent teams)?
Each MCP process automatically registers itself as a live session and
heartbeats while it runs. On a clean exit the session is removed at once
(a detached helper delivers the goodbye even while the host process is
being killed); if the process dies hard, the session expires ~10 minutes
after its last heartbeat. Three tools let the agent coordinate — session_list
is a core tool and always visible; session_update and session_end are
reached through the cf_tools gateway by default (or set
CONTEXTFORGE_TOOLS=full to see all three directly):
| Tool | What it does |
|---|---|
session_update | Declare what this session is working on ("working on the auth module") |
session_list | See other live sessions in the same project and their focus before touching shared areas (pass all_projects: true for the whole org) |
session_end | Explicitly end this session's presence (also automatic on exit) |
By default session_list is scoped to the current project — where work
actually collides. In a multi-project organization, pass all_projects: true
to see every session, or project: "<name-or-id>" to scope elsewhere.
Recommended pattern for your CLAUDE.md: call session_list when a
conversation starts; call session_update when starting or switching tasks.
You don't need to memorize commands — just talk naturally to your AI:
# Knowledge
"Save this: we use PostgreSQL for the main database"
"What database do we use?"
"List my spaces"
# GitHub
"Connect my repo github.com/myuser/myproject"
"What commits did I make today?"
"Show PRs merged this week"
# Issues
"Create an issue: Update the login page design"
"What's pending?"
"What should I work on next?"
"Mark the login issue as done"
| Variable | Required | Description |
|---|---|---|
CONTEXTFORGE_API_KEY | Yes | Your API key from the dashboard |
CONTEXTFORGE_API_URL | No | API endpoint (defaults to production) |
CONTEXTFORGE_DEFAULT_SPACE | No | Default space for operations |
CONTEXTFORGE_TOOLS | No | lean (default) exposes 11 tools — the 10 most-used plus the cf_tools gateway to the other 59. full exposes all 69, as versions before 0.11.0 did. Lean keeps ContextForge under Cursor's 40-tool cap and Claude Code's 50-tool degradation threshold. |
ContextForge MCP is a thin client that translates Model Context Protocol tool calls into authenticated HTTP requests against the ContextForge API. Your knowledge is stored, indexed (semantic embeddings), and retrieved on the server side — the MCP client itself is stateless.
This means:
Manage your memory visually at contextforge.dev:
# Clone and install
git clone https://github.com/alfredoizdev/contextforge-mcp.git
cd contextforge-mcp
npm install
# Build
npm run build
# Run tests
npm test
# Watch mode
npm run dev
Issues and pull requests are welcome at github.com/alfredoizdev/contextforge-mcp.
MIT © Alfredo Izquierdo
CONTEXTFORGE_API_KEY*secretYour API key from the ContextForge dashboard at contextforge.dev
CONTEXTFORGE_API_URLdefault: https://api.contextforge.devAPI endpoint URL (defaults to production)