Claude Checkpoint MCP

session-checkpoint-mcp

Save your Claude Code session state locally, so a crash, `/clear`, or context limit doesn't make Claude rebuild context from scratch.

session-checkpoint-mcp is a local Model Context Protocol server with three tools:

• save_session_checkpoint writes your session's working state to a small JSON file in the project.
• load_session_checkpoint turns that file back into a compact resume brief.
• list_session_checkpoints lists the checkpoints in the project, so you can pick which session to resume.

Each Claude Code session gets its own checkpoint, so several sessions can share a directory without overwriting each other.

It runs entirely on your machine. Nothing is sent anywhere.

Fork of tenlean/claude-checkpoint-mcp by Tenzin. The repository keeps that original name. The server is published as session-checkpoint-mcp, and the Claude Code plugin is session-checkpoint.

Contents

• Why: stop paying twice for the same context
• How it works
• Installation
• Configuration
• Environment variables
• Claude Code
• Claude Desktop
• Other MCP clients
• Usage
• Tool reference & examples
• The checkpoint files
• Security & privacy
• Troubleshooting
• Development

Why: stop paying twice for the same context

A long Claude Code session builds up a lot of context:

• what you're trying to do;
• which approaches already failed;
• which files matter;
• which test is still red.

Several things can wipe that out mid-task:

• a terminal crash, SSH drop, or laptop sleep;
• running out of context window;
• a /clear to get a fresh window.

The next session starts cold. To get back to where you were, Claude has to rebuild that context:

• Re-reading files to work out what was changed and why. Every file read is input tokens.
• Re-running exploration: grep, git diff, ls, test runs, all just to rediscover state.
• Re-explaining. You retype the goal, the constraints, and the dead ends, or Claude rediscovers the dead ends the hard way.

Each of those turns resends the growing conversation as input, so the cost compounds.

`session-checkpoint-mcp` swaps that rebuild for one small, structured read:

The resume brief for a typical session is about 1.2 KB of markdown, a few hundred tokens. The example below is real output at that size.

The biggest saving comes from drift detection. At save time, the server records a content hash for every file with uncommitted changes. On load, it compares those hashes against the working tree and tells Claude exactly which files changed after the checkpoint. Everything else in the brief can be trusted as-is, so Claude re-reads only what it has to.

How it works

  Session 1                                     Session 2 (after crash / /clear)

───────── ──────────────────────────────── Claude ──save_session_checkpoint──┐ ┌──load_session_checkpoint── Claude goal, tasks, summary, │ │ compact markdown brief next steps, decisions, ▼ │ + "changed since checkpoint" files, commands ┌─────────────────────┐ │ / │ server adds: │ .claude-checkpoint │◀── git: branch, HEAD, git branch/HEAD, │ .claude-checkpoint │ dirty files + hashes dirty files + hashes, │ .prev (backup) │ redacts secrets └─────────────────────┘

• Claude supplies the meaning: the goal, progress, decisions, next steps, and which commands mattered.
• The server supplies the facts: git branch and HEAD, every uncommitted or untracked file with its content hash, and timestamps.
• The server instructions teach Claude when to act. Claude is told to load at the start of a session and to save after milestones, before risky operations, and when the conversation gets long. It doesn't need to be prompted every time.

One checkpoint per session

Claude Code passes each MCP server its session id (CLAUDE_CODE_SESSION_ID). The server uses it to give every session its own file, /.claude-checkpoints/ .json, so sessions that share a directory (/tmp, or wherever you run claude agents) never overwrite or merge into each other.

• Saving always writes the current session's own file.
• Loading returns the session's own checkpoint if it has one. Otherwise, if other checkpoints exist, it returns a list (goal, last-saved time, branch, whether all tasks are done) and Claude asks you which one to resume. It never picks one for you, even when there's only one.
• Resuming another session's checkpoint loads it, but saves still go to the current session's own file, starting from what was loaded and recording where it came from (resumedFrom). The original is never modified.
• Checkpoints are kept until you delete them, so an old session can be resumed later.
• Clients without a session id (e.g. Claude Desktop) use the single /.claude-checkpoint file, exactly as before. A .claude-checkpoint left by an earlier version shows up in the list as legacy.

The session id an MCP server sees is the one it was started with:

Installation

Requirements: Node.js 20+ and git. Git is optional, but without it you lose drift detection.

git clone https://github.com/daniel-munoz/claude-checkpoint-mcp.git

cd claude-checkpoint-mcp npm install npm run build

The server entry point is now at dist/index.js.

From npm. The server is also published as session-checkpoint-mcp. In any of the configurations below, you can replace node /absolute/path/to/claude-checkpoint-mcp/dist/index.js with npx -y session-checkpoint-mcp:

claude mcp add --scope user checkpoint -- npx -y session-checkpoint-mcp

(The npm package claude-checkpoint-mcp is the upstream project's 0.1.0 release, not this fork.)

Configuration

Environment variables

Claude Code

As a plugin (easiest). This repo is also a Claude Code plugin marketplace. You don't need to clone or build anything:

claude plugin marketplace add daniel-munoz/claude-checkpoint-mcp

claude plugin install session-checkpoint@daniel-munoz

Restart Claude Code, then /mcp should show plugin:session-checkpoint:session-checkpoint as connected.

Upgrading from 0.2.x or earlier? The plugin was renamed from claude-checkpoint-mcp to session-checkpoint in 0.3.0, because Claude Code reserves the claude- prefix for its own plugins. Uninstall the old plugin and install the new one:

`sh

claude plugin uninstall claude-checkpoint-mcp@daniel-munoz

claude plugin marketplace update daniel-munoz

claude plugin install session-checkpoint@daniel-munoz

`

The full tool names changed from mcp__plugin_claude-checkpoint-mcp_claude-checkpoint__* to mcp__plugin_session-checkpoint_session-checkpoint__*. Update any permission allowlists in settings.json, hooks, or instructions that use the old names. Short names such as save_session_checkpoint and your existing checkpoint files are unaffected.

Manual setup. If you cloned the repo, register the server once for your user account, so it's available in every project:

# Run from the claude-checkpoint-mcp directory

claude mcp add --scope user checkpoint -- node "$PWD/dist/index.js"

Use an absolute path. A user-scoped server is launched from whichever project you open Claude Code in. A relative path like ./dist/index.js would resolve against *that* project, not this repo. "$PWD/dist/index.js" expands to the absolute path when you run the command, which is what gets saved.

Check that it's registered:

claude mcp list

Inside a session, /mcp should show checkpoint as connected.

Project-scoped alternative. To share the server with a team through version control, add it to the project's .mcp.json:

{

"mcpServers": { "checkpoint": { "command": "node", "args": ["/absolute/path/to/claude-checkpoint-mcp/dist/index.js"] } } }

Either way, add the checkpoint files to the project's .gitignore, or to your global gitignore:

.claude-checkpoint*

Claude Desktop (claude_desktop_config.json)

Open the config file:

Add the server under mcpServers, using the absolute path to your local build:

{

"mcpServers": { "checkpoint": { "command": "node", "args": ["/absolute/path/to/claude-checkpoint-mcp/dist/index.js"], "env": { "CHECKPOINT_PROJECT_ROOT": "/absolute/path/to/your/project" } } } }

Restart Claude Desktop after saving the file.

Claude Desktop has no notion of a "current project". Use CHECKPOINT_PROJECT_ROOT to set the default project, or have Claude pass projectRoot on each call (*"save a checkpoint for /home/me/code/my-app"*). See project root resolution.

Other MCP clients

Any MCP client that supports the stdio transport can run the server:

node /absolute/path/to/claude-checkpoint-mcp/dist/index.js

or

npx -y session