Knowledge & memory: MCP servers, A2A agents and x402 APIs

Long-term memory, knowledge bases and retrieval for agents: notes, wikis, graphs and semantic search. 265 listings in the Rooms directory, 264 answering our latest daily check. Each one links to its endpoint, how to call it and its live status.

Locul Cloud Memory Live MCP
Recall memories, entity profiles and source notes from your Locul cloud brain in any AI chat.
MCP server · ai.locul
Lodekeep Live MCP
Memory MCP server for Claude Code. Correct a fact and the old version stops being recalled.
MCP server · com.lodekeep
Machine Library (Space Frontiers) Live A2A
Research and commerce agent for the Machine Library knowledge platform by Space Frontiers Company: answers research questions grounded in multi-billion scholarly and public-interest documents with citations, explains MC…
A2A agent · Space Frontiers · 3 skills
madoromi.fun Live x402
Japanese dream-interpretation agent API. Returns a Gemini-generated full interpretation from madoromi's curated dream-motif knowledge base (result schema agent-dream-insight.full.v1). Japanese output only. Dream text is…
x402 paid API · 1 endpoint
Malaysia Open Data MCP Server Live MCP
This MCP server provides seamless access to Malaysia's government open data, including datasets, weather forecasts, and public transportation information. Enable efficient querying and retrieval of real-time and histori…
MCP server · hithereiamaliff
marginalia Live A2A
A persistent, memory-graph-backed chat agent. Send it a message; it replies with context drawn from its own evolving memory across past sessions. It also keeps projects it researches over time and can fold your contribu…
A2A agent · Polycode Limited · 3 skills
marketplaceforaiagents.com Live x402
Google Search API: Give a query, get ranked organic results with title, link, snippet, plus knowledge graph and related searches. $0.003 USDC per call on Base. (2 paid endpoints on marketplaceforaiagents.com.)
x402 paid API · 2 endpoints
Mash Prime Live MCP
Read Mash Prime's essays and build notes on agentic systems, memory, approvals, and workflows.
MCP server · dev.mashprime
mcp.whitemagic.dev Live x402
WhiteMagic hosted recall: read-only hybrid memory search (BM25 + vector + associative) over a curated public corpus for agent continuity. Call when an agent needs durable context from prior sessions or the public knowle…
x402 paid API · 1 endpoint
Memchats Live MCP
Search your chat history and contact memory, and ask advisors about your conversations.
MCP server · com.memchats
Memocore Live MCP
Shared memory for all your AI agents, your whole team and every MCP client — save, search, recall.
MCP server · ai.memocore
MemoryPlugin Live MCP
Give every AI you use one shared, permanent memory. Store once, recall in whichever AI you open.
MCP server · com.memoryplugin
MeshMarket Live MCP
The agent-to-agent capability exchange — rent memory, reasoning and safety, settled per call.
MCP server · io.github.RightOnPar-LLC
midax402.com Live x402
MIDAX402: Evidence+ x402 intelligence with expanded corpus retrieval, local risk brief, contradiction scan and concrete action plan. We do not grade our own answer: the verdict is answered or needs_more_data (grounded i…
x402 paid API · 1 endpoint
Mnemos — memory as a service Live MCP
Bi-temporal memory-as-a-service and paid agent labor. Pay-per-call USDC via x402; signed receipts.
MCP server · com.virohanalife
Mochii work graph Live MCP
Mochii work graph: projects, tasks, meetings. Stiki OAuth. Not Nexus memory.
MCP server · com.chibitek
MoonlyBox MoonLink Live MCP
Personal knowledge MCP: capture bookmarks, notes & todos by chat; archive pages; search memory.
MCP server · cn.moonlybox
mosADD — the comms layer for AI agents Live MCP
Command your AI agents by voice: PTT rooms, channels, direct messages, agent email, memory (mRAG).
MCP server · com.mosadd
MustertheForce MCP Live MCP
Salesforce-grounded retrieval, diagnoses, and a vetted-Force marketplace for MCP clients.
MCP server · com.mustertheforce
MyAITwin Live MCP
A personal RAG database you build from chat, so AI creates work that sounds like you.
MCP server · com.lutolearn
Naumu Live MCP
Search, extend, and act on your team's Naumu knowledge graph: notes, threads, and nodes.
MCP server · ai.naumu
Newsmind Live MCP
Read, search and track your RSS feeds: semantic search, story clustering, watches, OPML import.
MCP server · app.newsmind
NexTool MCP for GLPI Live MCP
MCP server for GLPI: tickets, ITIL, assets, knowledge base. GLPI 10/11. Not affiliated with Teclib'.
MCP server · com.nextoolsolutions
Nexus Memory Live MCP
Owner-scoped Nexus memory: search, facts, captures, KYC. Not Mochii's work graph.
MCP server · com.chibitek
Nysa Live MCP
Shared memory for teams that work with AI agents: meetings, email and calendar in one brain.
MCP server · com.usenysa
ONES Live MCP
Manage ONES projects, issues, tests, work hours, and Wiki knowledge.
MCP server · com.ones
paper-search-mcp-openai-v2 Live MCP
Find and download academic papers from leading sources like arXiv, PubMed, bioRxiv, medRxiv, Google Scholar, Semantic Scholar, CrossRef, and IACR. Get standardized results and fetch full-text PDFs when available. Accele…
MCP server · TitanSneaker
particle.pro Live x402
Search entities. Find a person, company, or knowledge graph entity by free-text query — a name, partial name, nickname, stock ticker, @handle, or website domain. (19 paid endpoints on api.particle.pro.)
x402 paid API · 12 endpoints
Penny Live MCP
Portable AI memory you own. Keep memories and notes across Claude, ChatGPT, and other AI tools.
MCP server · ai.mypenny
Perfect Memory Live MCP
Search what you've seen on screen and heard in meetings, recorded on your own Mac or PC.
MCP server · ai.perfectmemory
Picsha AI Live MCP
AI-native digital asset management: semantic search, generative image edits, and CDN delivery.
MCP server · ai.picsha
posttosource.com Live x402
Convert a Twitter/X, LinkedIn, Medium, Substack, Beehiiv, or public Notion page URL into clean markdown.
x402 paid API · 1 endpoint
Prowlo — Reddit & X for AI agents Live MCP
Reddit & X data for AI agents over MCP. Semantic search, hosted, no Reddit API.
MCP server · com.prowlo
Quelvio Live MCP
**Your company's brain for AI agents.** Quelvio continuously understands your organization's knowledge across every connected system — what's authoritative, what's recent, what's persistent, what's temporary, and what s…
MCP server · quelvio
RagSphere Live A2A
Secure RAG agent for PDF, Excel, and YouTube analysis with rate limiting and API key protection.
A2A agent · RagSphere Team · 2 skills
Recordo: Task Planner & Notes Live MCP
Brain dump, routines, task planning, focus, and instant thought retrieval
MCP server · app.recordo.api
RepoFold Live MCP
A cited wiki of your GitHub repo: search, read pages, find symbols and ask, with line citations.
MCP server · dev.repofold
ResponseHub Live MCP
Answer security questionnaires and RFPs from your AI knowledge base.
MCP server · ai.responsehub
Revelara Live MCP
Reliability intelligence: production incidents, risk register, controls catalog, knowledge graph.
MCP server · ai.revelara
RFP.ai Live MCP
Draft cited RFP and security questionnaire answers from your knowledge base, with human review
MCP server · ai.rfp
robbiegeorgephotography.com Live x402
Atomic canonical resolution for the registered Robbie George Biography Plate™ identifier. x402 payment grants one endpoint-level retrieval only. It does not grant training, embedding, bulk ingestion, redistribution, res…
x402 paid API · 1 endpoint
scopeapi.dev Live x402
Generate text embeddings and semantic embedding vectors using OpenAI text-embedding-3-small for vector search, semantic similarity, clustering, retrieval, and RAG workflows. (12 paid endpoints on scopeapi.dev.)
x402 paid API · 12 endpoints
Seturos Live MCP
Shared work memory for Claude Code, Codex, Cursor and chat, scoped to each repository.
MCP server · com.seturos
Sooveryn Live MCP
AI personas with a lasting, encrypted memory per project, for Claude Code. Hosted in France.
MCP server · com.sooveryn
Stele Live MCP
Shared project memory for AI coding agents: decisions, lessons, risks and tasks in one graph.
MCP server · dev.stele-ai
Suzuri Live MCP
Semantic search across Japan's government white papers, in English or Japanese. Free beta.
MCP server · dev.suzuri
Synapse Layer — Trust Infrastructure for AI Agents Live MCP
MCP-native Trust Infrastructure for AI Agents. Persistent encrypted memory with Trust Quotient.
MCP server · io.github.SynapseLayer
Syntology Live MCP
Provenance-tagged knowledge graph of AI/ML research: papers, citations, methods, code.
MCP server · ai.syntology

Related capabilities

x402 paid APIs AI models & inference Research Agent infrastructure Documents & PDFs Email Video & audio Coding & dev tools

How to use one

MCP servers plug into Claude, ChatGPT, Cursor and other AI clients; A2A agents take tasks over JSON-RPC; x402 APIs charge per call in USDC with no account. Guides: A2A vs MCP · How to call an A2A agent · x402 for agents.

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