AgentToolDrop

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Letta

Runs stateful agents that keep memory and identity across sessions and rewrite their own memory over time

Install with npm

npm install -g @letta-ai/letta-code

Copied from the project's docs at github.com/letta-ai/letta

Why you'd want it

Letta (formerly MemGPT) is now built as Letta Code, an agent harness whose agents keep memory, identity and conversation history and improve by rewriting their own memory blocks, skills and prompts. All context, including memory blocks, is tracked in git (MemFS), and agents can search past messages, call subagents and run on schedules. You reach the same agent from a terminal UI, a desktop app for macOS, Windows and Linux, chat.letta.com, or Slack, Telegram and Discord, with agent state stored in Letta Cloud or kept local.

Best for

  • Long-running personal or team agents
  • Agents that should learn from past sessions
  • Using one agent across terminal, desktop and chat apps

Use it when

You want a ready-made agent that remembers and adapts over long periods, rather than a memory library to wire into your own agent.

Skip it if

You need the older Letta V1 API server, which is retired to the repo's archive branch. Letta Cloud is the default backend, and remote computers and secrets require signing in with Letta.

Editor's note

The letta-ai/letta repo now only points to letta-ai/letta-code, where current development happens and which this entry tracks; the V1 server is on the old repo's archive branch.

Related tools

Same category or shared tags, by drop score.

  1. Rank 7

    OpenCode

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    Runs an open-source coding agent in your terminal, desktop app or browser with the LLM provider you choose

    • score 82
    • 214k stars
    • pushed
    • v1.19.0 on
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    Install OpenCode 2 with npm

    npm install -g @opencode/cli
    Use it when, skip it if, stats for OpenCode

    Why you'd want it

    OpenCode has two built-in agents you switch between with Tab: build, with full access for development work, and plan, which is read-only, denies file edits by default and asks before running bash commands. It supports many LLM providers out of the box, connected from the TUI with /connect, and extends through MCP servers, plugins, agent skills and custom commands. The team also sells OpenCode Go, a subscription for open-source models, but you can use your own provider keys instead.

    Best for

    • Terminal users who want provider choice
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    Use it when

    You want an MIT-licensed coding agent that works with many model providers and offers a TUI, a desktop app and a local web interface.

    Skip it if

    You install CLI tools through Windows package managers, which OpenCode 2 does not support; also note OpenCode 1 and 2 cannot be installed side by side under the default command.

    Stats

    Stars
    213,542
    Last push
    Release
    v1.19.0,
    License
    MIT
    Pricing
    Open source
    Works with
    macOS, Linux, Windows, Web, Docker
    Drop score
    82 of 100

    Full stat block for OpenCode

  2. Rank 19

    Mem0

    Memory

    Adds long-term user, session and agent memory to AI apps through a Python or TypeScript SDK

    • score 66
    • 67.2k stars
    • pushed
    • ts-v3.3.1 on
    • Apache-2.0

    Install with pip

    pip install mem0ai
    Use it when, skip it if, stats for Mem0

    Why you'd want it

    Mem0 extracts facts from conversations with an LLM call and stores them so later turns can search them by user, session or agent. Retrieval combines semantic search, BM25 keyword matching and entity linking, with time-aware ranking for questions about current state versus past events. You can run it as a library from pip or npm, as a self-hosted server with a dashboard and API keys through Docker Compose, or on the managed Mem0 Platform.

    Best for

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    • Remembering user preferences across sessions
    • Starting with a library and moving to a managed service later

    Use it when

    Your agent should remember facts about users or its own past actions between conversations without you designing the storage and retrieval.

    Skip it if

    You want memory with no LLM or embedding calls: Mem0 requires an LLM and defaults to OpenAI models. The README notes its benchmark scores come from the managed platform, which includes optimizations not in the open-source SDK.

    Stats

    Stars
    67,205
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    Release
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    License
    Apache-2.0
    Pricing
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    Drop score
    66 of 100

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  3. Rank 43

    goose

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    Runs a general-purpose AI agent on your machine as a desktop app, CLI or embeddable API

    • score 57
    • 55.3k stars
    • pushed
    • v1.54.0 on
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    Install the CLI with the install script

    curl -fsSL https://github.com/aaif-goose/goose/releases/download/stable/download_cli.sh | bash
    Use it when, skip it if, stats for goose

    Why you'd want it

    goose is a local agent for code as well as research, writing, automation and data analysis, available as a desktop app for macOS, Linux and Windows, a CLI and an API. It works with 15+ providers including Anthropic, OpenAI, Google, Ollama, OpenRouter, Azure and Bedrock, and can use existing Claude, ChatGPT or Gemini subscriptions through ACP. It connects to 70+ extensions over MCP, and you can build custom distributions with preconfigured providers, extensions and branding.

    Best for

    • Agents for tasks beyond coding
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    Use it when

    You want an open-source local agent that is not tied to one model vendor and that you extend with MCP servers.

    Skip it if

    You want a coding agent built into your IDE; goose runs as its own desktop app or CLI.

    Stats

    Stars
    55,288
    Last push
    Release
    v1.54.0,
    License
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    Pricing
    Open source
    Works with
    macOS, Linux, Windows
    Drop score
    57 of 100

    Full stat block for goose

For agents

The same entry, as files an agent can read without scraping this page. 

# read one entry
curl -s https://agenttooldrop.com/tools/letta.md

# list the MCP servers in the catalog
curl -s https://agenttooldrop.com/tools.json \
  | jq -r '.tools[] | select(.category=="mcp-server") | .slug'