Muscle-mem: AI uses the brain to direct the cerebellum, solidifying thinking into conditioned reflexes

Written by
Iris Vance
Updated on:June-28th-2025
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New breakthroughs in AI technology allow machines to perform tasks as accurately as the cerebellum.
Core content:
1. Introduction to the Muscle-mem project and its position in the AI ​​architecture
2. The division of labor between the "brain" and "cerebellum" of the AI ​​system, and its impact on efficiency and cost
3. Muscle-mem's technical implementation and core capabilities, how to optimize AI's execution efficiency

Yang Fangxian
Founder of 53AI/Most Valuable Expert of Tencent Cloud (TVP)

I was recently thinking about the architecture of MCP gateway and MCP cache, and then I saw such a project on Github, which is somewhat similar to the expected MCP cache concept:


Project address: https://github.com/pig-dot-dev/muscle-mem


In the era of big models, AI agents have powerful understanding and reasoning capabilities, and seem to be omnipotent. However, in real enterprise scenarios, we often find that they are "not very useful":

  • For the same task, the operation is different each time and the result is uncertain;

  • Large models are “smart” but inefficient, costly, and poorly controllable;

  • More importantly, it thinks more and does less .

The emergence of Muscle-mem is a crucial step on the path from intelligence to capability, from model to system.


Brain vs. Cerebellum: Understanding the Division of Labor in AI Architecture from the Perspective of the Nervous System 8


When humans complete a precise and high-speed action - such as dunking, writing quickly, and playing the piano - it is not the brain that they rely on, but the cerebellum.

  • Brain : responsible for thinking, reasoning, and judgment, and is the "cognitive center";

  • Cerebellum : responsible for action coordination, path memory and repeated execution, it is the "action factory";

  • Hands and feet : are the terminal executors of the hardware.


There is a similar division of labor in AI systems:

  • Large Model (LLM) : Like the brain, it is good at perception, analysis, and generation;

  • Muscle-mem : MCP cache, plays the role of "cerebellum", once learning is completed, it completes the task quickly, stably and accurately;

  • Toolchain/Peripherals/API : These are the “hands and feet” of the AI ​​system.

The significance of muscle-mem is to add a "cerebellum" to AI - instead of having to "rethink" every time, it can automatically reuse and quickly execute what has been thought of and done correctly.

Design philosophy: Find a balance between certainty and flexibility


The core goal of muscle-mem is to remove LLM from the "hot path" of repetitive tasks and instead quickly replay the learned operation path through a cache mechanism. This is similar to the "muscle memory" that humans achieve through the cerebellum after learning new skills - fast execution in a familiar environment without rethinking.

This design concept stems from the observation of the "long tail environment":

  • Long-tail environments : refer to those environments that are predictable most of the time but occasionally have anomalies.

In this environment, traditional automation scripts (such as RPA) are efficient in handling routine tasks but tend to fail when faced with abnormal situations; while agents that rely entirely on LLM are flexible but costly and slow.

Muscle-mem aims to combine the advantages of both: fast and stable execution through caching mechanism in regular tasks; when encountering abnormal situations, fall back to LLM for processing.

Muscle-mem is an open source framework that provides "behavior caching" capabilities for AI agents. It records the tool call sequence, parameter path, and context environment when the agent completes a task, and quickly reuses it when the environment is consistent.

Core capabilities include:

  • Semantic level path matching and verification

  • Cache hit means automatic replay of task path

  • Falling back to LLM reasoning on cache miss

  • Automatically update the cache after the path is successfully executed


It does not replace LLM, but solidifies the process of "doing it" after LLM has "figured it out" , just like the cerebellum, so that "repetitive tasks no longer waste cognitive resources."

Technical implementation: behavior caching and environment verification


The implementation of muscle-mem includes the following key components:

  1. Task path recording : records the tool call sequence and parameters of the agent when completing the task.

  2. Environment context binding : associates information such as input parameters and environment characteristics during task execution with the operation path.

  3. Cache validation mechanism : When the task is triggered again, the consistency between the current environment and the cache environment is compared to decide whether to use the cache path.

  4. Failure fallback mechanism : If the cache path execution fails, it automatically falls back to LLM for re-reasoning and updates the cache.

This mechanism ensures that when the environment has not changed significantly, the system can quickly replay the verified operation path; when the environment changes significantly, the system can respond flexibly and maintain a balance between stability and flexibility.


Why it’s important: It gives AI “system engineering attributes”


Muscle-mem is designed to be particularly suitable for the following scenarios:

  • Automation of repetitive tasks : such as form filling, data migration, etc., can improve efficiency through caching mechanism.

  • Legacy system integration : In old systems that lack APIs, automated control can be achieved by recording operation paths.

  • Resource-constrained environment : When computing resources are limited, reduce the calls to LLM and reduce costs.

Through applications in these scenarios, Muscle-mem has achieved the transition from traditional automation to intelligence, providing enterprises with more efficient and flexible solutions.

In actual enterprise implementation, the value of Muscle-mem far exceeds "efficiency improvement":

Traditional Agent Problem
Muscle-mem solution
LLM reasoning is required every time, which is costly
Cache successful paths to reduce call frequency
The execution results of the same task are unstable
Conditional replay for deterministic execution
Lack of modularity and cannot be reused
Each successful task path becomes a "soft component"
Difficult project deployment and inability to access old systems
Can be embedded in unstructured environments such as UI, scripts, command lines, etc.


Muscle-mem makes AI Agent no longer just a "conversational interface", but a business system component that can be automatically generated, verified, solidified, and reused .

From AI to "Software Factory": The Beginning of New Industrial Logic


The deeper significance of Muscle-mem is that it promotes the industrialization trend of "AI generation systems".

We are seeing a new paradigm emerging:

  • The big model is responsible for thinking and reasoning

  • Muscle-mem is responsible for learning and solidifying the path

  • Tools and interfaces to perform operations

  • The whole process continuously feeds back and evolves automatically

This is a new automation architecture that uses LLM as the cognitive engine, behavior cache as the core memory, and Agent as the system shell. Every successful execution path is a piece of "verified software."

These paths can be standardized, modularized, decentralized and shared , ultimately building a "memory network" consisting of tens of millions of micro AI modules.


Memory Networks: When AI Capabilities Circulate Like Software


Once successful paths are cached, they can be organized and shared. In the future, we can even build an "Agent Cache Registry" to achieve "functional reuse" across enterprises and applications:

  • The reimbursement agent path of Company A is quickly called by Company B;

  • The high-frequency operation paths of a certain industry are openly shared by the industry association;

  • The user-contributed paths are tested and authenticated to form a “trusted cache module”.

This is very similar to the collaborative logic of open source software and the idea of ​​"node consensus" in blockchain. Muscle-mem is the memory layer, solidification layer and value precipitation layer.


Conclusion: The era of AI’s “engineering hardening” is quietly approaching


The significance of muscle-mem is not just to make the agent execute faster - it also represents a system-level cognitive leap:

From "flexible generation" to "stable execution", from "thinking model" to "functional module", from "general intelligence" to "engineering capability".

It is like the human "cerebellum", which no longer thinks over and over again, but allows AI to perform tasks with ease and precision in familiar scenarios; it is a layer of cache that precipitates AI's past "experience" into operational paths that can be directly called; it is a converter that converts probabilistic reasoning into a controllable system, allowing "AI's thinking" to truly become "business actions."