Protocol Specification
Mesh Memory Protocol (MMP)
A Mesh Protocol for Collective Intelligence
| Version | 0.2.3 |
| Status | Published |
| Date | 17 April 2026 |
| Author | Hongwei Xu <hongwei@sym.bot> |
| Organisation | SYM.BOT |
| Canonical URL | https://sym.bot/spec/mmp |
| Licence | CC BY 4.0 (specification text); Apache 2.0 (reference implementations) |
Introduction
AI agents today run in isolation. They share data through message buses, API calls, or shared databases — but they do not think together. A coding agent, a music agent, and a fitness agent serving the same user each see their own domain. No single agent connects “commits slowing” + “tracks skipped” + “3 hours without movement” into “the user is fatigued.” That insight requires collective intelligence — and no existing protocol provides it.
The Mesh Memory Protocol (MMP) defines how autonomous AI agents discover each other, exchange cognitive state, evaluate incoming signals for per-field relevance, and remix each other’s observations into new understanding — without servers, without central coordination, and without sharing raw data. Memory is not copied between agents. It is remixed: each agent processes incoming signals through its own domain intelligence and produces something new.
MMP operates over TCP on local networks and WebSocket for internet relay, with length-prefixed JSON as the canonical wire format. Discovery uses DNS-SD (Bonjour) with zero configuration. The protocol is specified across 8 layers — from identity and transport (Layers 0–3) to cognitive coupling via SVAF (Symbolic-Vector Attention Fusion, the per-field evaluation engine at Layer 4), synthetic memory, and per-agent neural networks (Layers 5–7). Together, the upper layers form Mesh Cognition: a closed loop where agents reason on the growing remix graph of immutable Cognitive Memory Blocks.
Status of This Document
This is a published specification. It reflects the protocol as implemented in the reference implementations (SYM Node.js and SYM Swift). The specification is versioned. Breaking changes increment the minor version; non-breaking additions increment the patch version.
Feedback and errata: spec@sym.bot or github.com/sym-bot/sym/issues.
Implementations
| Language | Project | Maintainer | Scope |
|---|---|---|---|
| Node.js / TypeScript | sym-bot/sym | SYM.BOT | Reference implementation. Full protocol surface (Layers 0–7). |
| Swift | sym-bot/sym-swift | SYM.BOT | Reference implementation. macOS / iOS. Full protocol surface. |
Change Log
| Version | Date | Changes |
|---|---|---|
| 0.2.3 | 2026-04-17 | Section 13.9 — Compact Channel Best Practices: CMB envelope header convention (RECOMMENDED) for structured message headers with signal keywords and focus tags. Lazy-load channel pattern (RECOMMENDED) for MCP server implementations: compact header push with on-demand full-content retrieval via sym_fetch, reducing mesh-traffic context consumption by ~75%. Token-count hint RECOMMENDED. Rolling message store with RECOMMENDED default of 200 messages. Signal-keyword priority table (informational): HALT > DIRECTIVE > RESULT > ACK. |
| 0.2.2 | 2026-04-06 | Section 11 — Feedback Modulation: how collective intelligence becomes self-correcting. Validator-authority CMBs with per-field reasoning modulate SVAF coupling weights and CfC temporal adaptation through the existing mesh cognition loop. Neuroscience-grounded: dopaminergic prediction error model with per-field direction and τ-modulated adaptation rate. Directive feedback for standalone domain knowledge injection. Validator-origin anchor weight 2.0 with role-grant verification. CfC state persistence across restarts. ABNF wire format grammar. CMB forward compatibility. Multi-relay failover. All cognitive content MUST use cmb frames. |
| 0.2.1 | 2026-04-02 | Node model: every autonomous agent MUST be a full peer node with own identity, coupling engine, and memory store. SVAF band-pass evaluation: four-class model (redundant/aligned/guarded/rejected) with per-field redundancy detection. CMB lifecycle: observed/remixed/validated/canonical/archived with anchor weight progression. Node lifecycle roles (observer/validator/anchor) with identity-bound validation authority and earned role progression. Validation authority for CMB lifecycle transitions bound to cryptographic node identity, not content. Semantic encoder SHOULD for SVAF drift computation. Handshake adds version, extensions, and lifecycleRole fields. Error frame type. Role-grant frame type. |
| 0.2.0 | 2026-03-27 | Formal specification published. 8-layer architecture. CAT7 CMB schema with lineage (parents + ancestors). SVAF per-field evaluation. Wire format normatively specified. Error frame. Frame type registry. Extension mechanism. JSON Schema. Connection state machine. Wire examples. |
| 0.1.0 | 2025-08-01 | Initial protocol design (Consenix Labs Ltd). 4-layer architecture. Scalar drift evaluation. |
Licence
This specification is published under the Creative Commons Attribution 4.0 International Licence (CC BY 4.0). You may share, adapt, and build upon this specification for any purpose, including commercial use, provided you give appropriate credit.
The reference implementations are published under the Apache Licence 2.0.
Mesh Memory Protocol, MMP, SYM, and related marks are trademarks of SYM.BOT.
© 2026 SYM.BOT. Specification text licenced under CC BY 4.0. Reference implementations licenced under Apache 2.0.