
Longmem
- 1 repo stars
- Updated April 17, 2026
- marerem/longmem
io.github.marerem/longmem is a MCP server that gives Cursor and Claude Code persistent cross-project memory via local semantic search.
About
io.github.marerem/longmem is an MCP server that adds persistent, cross-project memory for AI coding workflows in Cursor and Claude Code. Instead of losing architecture decisions, API quirks, and naming conventions when you close a chat or switch repositories, longmem stores and retrieves notes using local semantic search. Developers who juggle multiple products benefit because the agent can surface relevant prior context without you manually grep-ing old threads or README fragments. Install it when you ship with agent-first editors and want continuity from validation notes through build, review, and small-team operations. It is MCP integration layer tooling, not a hosted SaaS memory product, and it complements skills that plan or review code by giving those rituals something durable to read back. Version 0.2.1 runs over stdio from the published PyPI package longmem.
- Local persistent memory across projects with semantic search instead of brittle chat history
- stdio PyPI package (longmem) at version 0.2.1 for Claude Code and Cursor MCP config
- Cross-project recall so solo builders avoid repeating context dumps every new session
- Privacy-friendly local indexing versus sending full project history to a remote memory API
- Pairs with other dev MCP servers as the layer that remembers what those tools helped you decide
Longmem by the numbers
- Data as of Jul 7, 2026 (Skillselion catalog sync)
claude mcp add longmem -- uvx longmemAdd your badge
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| repo stars | ★ 1 |
|---|---|
| Package | longmem |
| Transport | STDIO |
| Auth | None |
| Last updated | April 17, 2026 |
| Repository | marerem/longmem ↗ |
What it does
Give Claude Code or Cursor durable recall of decisions, APIs, and context across repos without re-pasting the same notes every session.
Who is it for?
Best when you use Claude Code or Cursor on several codebases and want local, searchable agent memory without a third-party cloud notebook.
Skip if: Skip if you need audited enterprise knowledge bases, strict RBAC, or zero local indexing on locked-down machines.
What you get
After you register longmem, your agent can semantically recall stored context across projects so implementation and fixes start from accumulated memory instead of a blank slate.
- MCP-accessible store-and-search memory across configured projects
- Semantic retrieval of past decisions and notes inside agent sessions
- Reduced repeated context pasting when switching repos or chats
By the numbers
- Published package version 0.2.1 on PyPI identifier longmem
- stdio transport via MCP server schema 2025-12-11
- Targets Cursor and Claude Code per server description
README.md
Your AI solves the same bug in a different project six months later. Writes the same boilerplate. Explains the same pattern. You already knew the answer.
longmem gives your AI a persistent memory that works across every project and every session. Before reasoning from scratch, it searches what you've already solved. After something works, it saves it. The longer you use it, the less you repeat yourself.
You describe a problem
│
▼
search_similar()
┌─────────────────────────────────────────────────────┐
│ 1. pre-filter by category (ci_cd / auth / db / …) │
│ 2. semantic search (Ollama or OpenAI embeddings) │
│ 3. keyword search (SQLite FTS5 exact match) │
│ 4. merge + rank results │
└─────────────────────────────────────────────────────┘
│ │
score ≥ 85% score < 85%
│ │
▼ ▼
cached solution AI reasons from scratch
+ edge cases │
+ team knowledge "it works"
(any project) │
▼
confirm_solution()
saved once — surfaces
from every future project
Why longmem
| longmem | others | |
|---|---|---|
| Cost | Free — local Ollama embeddings | Requires API calls per session |
| Privacy | Nothing leaves your machine | Sends observations to external APIs |
| Process | Starts on demand, no daemon | Background worker + open port required |
| IDE support | Cursor + Claude Code | Primarily one IDE |
| Search | Hybrid: semantic + keyword (FTS5) | Vector-only or keyword-only |
| Teams | Export / import / shared DB path / S3 | Single-user |
| License | MIT | AGPL / proprietary |
Quickstart
1. Install
pipx install longmem
2. Setup — checks Ollama, pulls the embedding model, writes your IDE config
longmem init
3. Activate in each project — copies the rules file that tells the AI how to use memory
cd your-project
longmem install
4. Restart your IDE. Memory tools are now active on every chat.
Need Ollama? Install from ollama.com, then
ollama pull nomic-embed-text. Or use OpenAI — see Configuration.
How it works
longmem is an MCP server. Your IDE starts it on demand. Two rules drive the workflow:
Rule 1 — search first. Before the AI reasons about any bug or question, it calls search_similar. If a match is found (cosine similarity ≥ 85%), the cached solution is returned with any edge-case notes. Below the threshold, the AI solves normally.
Rule 2 — save on success. When you confirm something works, the AI calls confirm_solution. One parameter — just the solution text. Problem metadata is auto-filled from the earlier search.
The rules file (longmem.mdc for Cursor, CLAUDE.md for Claude Code) wires this up automatically. No manual prompting.
AI forgot to save? Run longmem review — an interactive CLI to save any solution in 30 seconds.
Cold start — getting value from day one
longmem is most useful once it has entries. The fastest way to seed it:
Option 1 — review as you go. After every solved problem this week, run longmem review and describe what you fixed. Ten entries is enough to feel the difference.
Option 2 — team import. If a teammate already has entries, they export and you import:
# teammate
longmem export team_knowledge.json
# you
longmem import team_knowledge.json
Option 3 — shared DB. Set db_path (or db_uri for S3/cloud) to the same location for the whole team. Every save is instantly available to everyone.
CLI
| Command | What it does |
|---|---|
longmem init |
One-time setup: Ollama check, model pull, writes IDE config |
longmem install |
Copy rules into the current project |
longmem status |
Config, Ollama reachability, entry count, DB size |
longmem export [file] |
Dump all entries to JSON — backup or share |
longmem import <file> |
Load a JSON export — onboard teammates or migrate machines |
longmem review |
Manually save a solution when the AI forgot |
longmem with no arguments starts the MCP server (used by your IDE).
Configuration
Config lives at ~/.longmem/config.toml. All fields are optional — defaults work with a local Ollama instance.
Switch to OpenAI embeddings
embedder = "openai"
openai_model = "text-embedding-3-small"
openai_api_key = "sk-..." # or set OPENAI_API_KEY
Install the extra: pip install 'longmem[openai]'
Team shared database
Point every team member's config at the same path:
# NFS / shared drive
db_path = "/mnt/shared/longmem/db"
Or use cloud storage:
# S3 (uses AWS env vars)
db_uri = "s3://my-bucket/longmem"
# LanceDB Cloud
db_uri = "db://my-org/my-db"
lancedb_api_key = "ldb_..." # or set LANCEDB_API_KEY
No shared mount? Use longmem export / longmem import to distribute a snapshot.
Team knowledge base
Save facts that are true across your whole stack under project="shared" so they surface from any repo:
save_solution(
problem="why oauth2-proxy uses port 4181 not default 4180",
solution="General: 4180 is the oauth2-proxy default. 4181 means something else already occupies 4180.\n\nThis team's setup: Sinfonia always runs on 4180. Every other project uses 4181+ by convention.",
project="shared",
category="networking",
tags=["oauth2-proxy", "ports", "nginx"]
)
search_similar searches all projects — a shared entry surfaces automatically from any repo without needing search_by_project.
Three-layer solution format — write solutions so they work for anyone who finds them:
| Layer | Scope | How to save |
|---|---|---|
| 1. General pattern | Universal — any team | always include in solution text |
| 2. Team-wide fact | Your whole stack | project="shared" |
| 3. Project detail | One repo only | project="<repo>" + enrich_solution |
Tuning
similarity_threshold = 0.85 # minimum score to surface a cached result (default 0.85)
duplicate_threshold = 0.95 # minimum score to block a save as a near-duplicate (default 0.95)
MCP tools
The server exposes 11 tools. The two you interact with most:
search_similar— semantic + keyword hybrid search. Returns ranked matches with similarity scores, edge cases, and akeyword_matchflag when the hit came from exact text rather than vector similarity.confirm_solution— saves a solution with one parameter. Problem metadata auto-filled from the preceding search.
Full list: save_solution, correct_solution, enrich_solution, add_edge_case, search_by_project, delete_solution, rebuild_index, list_recent, stats.
Call rebuild_index once you reach 256+ entries to compact the database and build the ANN index for faster search.
Category reference
Categories pre-filter before vector search — keeps retrieval fast at any scale.
| Category | Use for |
|---|---|
ci_cd |
GitHub Actions, Jenkins, GitLab CI, build failures |
containers |
Docker, Kubernetes, Helm, OOM kills |
infrastructure |
Terraform, Pulumi, CDK, IaC drift |
cloud |
AWS/GCP/Azure SDK, IAM, quota errors |
networking |
DNS, TLS, load balancers, timeouts, proxies |
observability |
Logging, metrics, tracing, Prometheus, Grafana |
auth_security |
OAuth, JWT, RBAC, secrets, CVEs |
data_pipeline |
Airflow, Prefect, Dagster, ETL, data quality |
ml_training |
GPU/CUDA, distributed training, OOM |
model_serving |
vLLM, Triton, inference latency, batching |
experiment_tracking |
MLflow, W&B, DVC, reproducibility |
llm_rag |
Chunking, embedding, retrieval, reranking |
llm_api |
Rate limits, token cost, prompt engineering |
vector_db |
Pinecone, Weaviate, Qdrant, LanceDB |
agents |
LangChain, LlamaIndex, tool-calling, agent memory |
database |
SQL/NoSQL, migrations, slow queries |
api |
REST, GraphQL, gRPC, versioning |
async_concurrency |
Race conditions, event loops, deadlocks |
dependencies |
Version conflicts, packaging, lock files |
performance |
Profiling, memory leaks, caching |
testing |
Flaky tests, mocks, integration vs unit |
architecture |
Design patterns, service boundaries, refactoring |
other |
When nothing above fits |
Contributing
Contributions are very welcome — this project grows with the community that uses it.
Whether it's a bug fix, a new feature, better docs, or just sharing your use case — all of it helps. If you're unsure whether an idea fits, open an issue first and we'll figure it out together.
Getting started:
git clone https://github.com/marerem/longmem
cd longmem
uv sync --group dev
uv run pytest
Good first contributions:
- New category suggestions
- Edge cases you hit in real projects
- IDE integrations (JetBrains, VS Code, Neovim, etc.)
- Better error messages
- Seed datasets — export your own entries and share them as a starter pack
Ways to contribute without code:
- Star the repo if you find it useful
- Share it with your team
- Open an issue if something is confusing — unclear UX is a bug
License
MIT — see LICENSE.
mcp-name: io.github.marerem/longmem
Recommended MCP Servers
How it compares
MCP memory integration with local semantic search, not a generic note-taking skill or hosted vector SaaS.
FAQ
Who is io.github.marerem/longmem for?
It is for developers and small teams on Cursor or Claude Code who want persistent, searchable context across multiple repositories without repeating long briefings.
When should I use io.github.marerem/longmem?
Use it once you rely on agents daily and notice the same project facts need to be re-stated after every chat reset or repo switch.
How do I add io.github.marerem/longmem to my agent?
Add the longmem PyPI package (0.2.1) as an stdio MCP server in your Claude Code or Cursor MCP settings, following the repository setup for your OS.