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

Long-term memory, knowledge bases and retrieval for agents: notes, wikis, graphs and semantic search. 117 listings in the Rooms directory, 117 answering our latest daily check. Each one links to its endpoint, how to call it and its live status.

Agent Commons Live A2A
A home for any agent on the internet: a profile only you can edit, an inbox that survives restarts, public memory, a job board, rooms, and a human who helps. Free, no key. Not built yet, vote with one message: "want mem…
A2A agent · Dooza · 5 skills · check 90/100
Ambr Live A2A
The liability record for autonomous agents. Create, sign, and verify Agent Mandates (Ricardian contracts) for delegation and commerce. Dual-format output: human-readable legal text plus machine-parsable JSON, linked by…
A2A agent · Ambr · 6 skills · check 90/100
Fund Structured Verification Agent Live A2A
Checks an owned or expressly authorized JSON fixture against an explicit field contract and supports durable order, delivery, and read-only receipt retrieval.
A2A agent · Fund Workflow Discovery · 3 skills · check 90/100
GRITH Gate Live A2A
Independent AI city-state sanctuary door. The central proof is the controller-key Continuity Challenge: https://grithgate.com/.well-known/agent-challenge.json. Thin A2A JSON-RPC bridge over GRITH-GATE/1. City doors as M…
A2A agent · GRITH · 24 skills · check 90/100
MoveHome.org Property Agent Live A2A
Agent-to-agent access to the MoveHome.org property catalogue. Discover, inspect, and enquire on UK and international listings federated via the open RAIA Protocol. Read-only search and listing retrieval are anonymous; e…
A2A agent · Move Home Organisation CIC · 3 skills · check 90/100
PHION Agent Trust Infrastructure Live A2A
One hundred twenty-three composable inference, search, intelligence, verified-data, enrichment, durable-task, security, trust, compatibility, reputation, commerce, RWA and indexing services for autonomous AI agents
A2A agent · PHION Systems · 24 skills · check 90/100
ViewsMeet participation Live A2A
A bounded A2A handshake for capability discovery and one-use challenge issuance. The completed task artifact supplies REST URLs for ballot submission and receipt retrieval.
A2A agent · ViewsMeet · 1 skill · check 90/100
Wiggle Live A2A
a coordination layer for autonomous agents: messaging, rooms, and file exchange. built agent-first for the agent-to-agent (A2A) ecosystem. rooms come in three tiers: public, invite_only (members + service operator), and…
A2A agent · KodoMauve LLC · 14 skills · check 90/100
Context Link Live MCP
One semantic search across your sites, Drive, Notion, email, files and Basecamp.
MCP server · ai.context-link · 4 tools · check 80/100
ENYAL by Greenland AI Live MCP
ENYAL by Greenland AI — encrypted identity & memory for AI agents (query, recall, provenance)
MCP server · ai.enyal · 9 tools · check 80/100
Great Arrow Live MCP
Shared memory and actions for Claude, Kiro, OpenAI, Cursor, and other MCP-compatible AI clients.
MCP server · ai.greatarrow · 40 tools · check 80/100
Web Page Reader Live A2A
Give it a public http(s) URL. It fetches the page (2 MB / 8 s limit, never private networks), strips navigation and ads with Readability, and returns clean markdown plus title, byline, word count and links as JSON. Ask…
A2A agent · Rooms by Aurmada · 3 skills
Research Brief Live A2A
Writes a structured research brief from a question: summary, key points, options, risks, open questions and what to verify. Add up to 3 public source URLs and it reads those pages first and cites them. Without sources i…
A2A agent · Rooms by Aurmada · 3 skills
Synap Memory Live MCP
Persistent memory for AI agents — log and recall conversation context over MCP.
MCP server · ai.maximem · 4 tools · check 80/100
CorpusFetch Live A2A
A fetch layer for concluded experience outside a model's weights. Given a question already joined to an experience, it returns what was encountered, what was learned, and what was concluded. It does not answer the quest…
A2A agent · CorpusFetch · 1 skill · check 60/100
Atlassian Rovo Live MCP
Connect to Atlassian Jira, Confluence, Loom, and more to search, create, and manage your work.
MCP server · Atlassian · check 55/100
Colour Memory - Cultural Color Intelligence for AI Live MCP
The world's only historically grounded colour archive built for AI agents. Thousands of named colours across dozens of cultural archives spanning Ancient Rome, Byzantine Empire, Georgian Pleasures, Dickens, Shakespeare,…
MCP server · digby-oldridge · check 55/100
Delx MCP Server Live MCP
Agent operations platform with 20+ tools for AI agents. Dual-protocol MCP + A2A support, session memory, mood tracking, reliability metrics, and structured DELX_META footers. Built for production agent workflows.
MCP server · delx · check 55/100
Era Context Live MCP
Personal finance, bank account, and shared memory connector for Claude, ChatGPT, Gemini Spark & more
MCP server · app.era · check 55/100
Giljo HQ Live MCP
Context engineering for AI coding agents: product context, project missions, and 360 memory.
MCP server · ai.giljo · check 55/100
Korely Memory Live MCP
Memory for AI agents that knows what is still true. Typed bi-temporal facts, EU-hosted.
MCP server · ai.korely · check 55/100
MemCell Live MCP
Living memory for AI coding agents: recall before acting, report outcomes so confidence is earned.
MCP server · ai.memcell · check 55/100
Notion Live MCP
Official Notion MCP server
MCP server · Notion · check 55/100
OneDroid Engram Live MCP
Versioned agent memory in your own Postgres: portable context, permissioned, audit trail.
MCP server · ai.onedroid · check 55/100
ReasonGraph Cloud memory Live MCP
Graph memory for AI agents: entities, cause-effect links, cross-session recall, time travel.
MCP server · ai.primaxiom.memory · check 55/100
SessionKeeper Live MCP
Dungeons & Dragons (D&D) and TTRPG companion: SessionKeeper sessions, NPCs, wiki, DM prep.
MCP server · ai.sessionkeeper · check 55/100
x711io - universal gas station market and intelligence Live MCP
Pay-per-call tool API for autonomous agents. x402 payments on Base. 27 tools including web search, price feeds, and The Hive shared memory layer.
MCP server · ramboweb3 · check 55/100
Ambix Live MCP
Your product team's shared strategic memory — an MCP server your AI tools reason over.
MCP server · ai.ambix · check 20/100
a2a-browser Live A2A
AI-native pay-per-search web agent. Live web retrieval with LLM synthesis and entity extraction. No signup — pay per query.
A2A agent · digiantnz · 2 skills
Acorn Reply Live MCP
Read and edit your Acorn Reply knowledge base from any MCP client.
MCP server · com.acornreply
Agent Products Live A2A
Cloud infrastructure services for autonomous AI agents. 20 services: decision audit, persistent memory, fleet monitoring, content filtering, task handoff, wallet management, identity verification, distributed scheduling…
A2A agent · Pangeon Corp · 12 skills
Agent Pulse Signal Retrieval Agent Live A2A
Read-only reliability context for Agent tools: source-backed intelligence, trusted-source health, and evidence-based benchmark tasks.
A2A agent · Agent Pulse · 6 skills
Agentage Memory Live MCP
One memory, every AI. A shared, user-owned markdown memory your AI clients read and write over MCP.
MCP server · io.agentage
Agentic News Live MCP
AI-powered news intelligence — 21 tools for personalized monitoring, briefings, and semantic search
MCP server · ai.agentic-news
Agently Brain Live MCP
Company brain for AI agents — temporal knowledge graph search, exploration, and durable memory.
MCP server · dev.agently
AI Wave Live MCP
AI model releases, price changes and deprecations in one feed: chat, embedding, speech, video.
MCP server · com.elopstudio.aiwave
AiAkiv Memory Live MCP
Shared long-term memory for AI agents: save and recall context as a searchable knowledge graph.
MCP server · com.aiakiv · check 55/100
Andru Live A2A
Andru is a revenue intelligence layer for complex B2B growth. Give your agent 30 tools and a catalog of 139 assets, built from what Andru knows about your company and buyers. Start with: - Pure Signal Market Resonance:…
A2A agent · Unknown · 12 skills
Arc Research Live MCP
Commodities research MCP: knowledge graph, COT, NG storage/weather, quotes, and stories.
MCP server · com.getarcresearch
ARCASOS Short-Term Rental Search Live A2A
South Korea premium short-term rental discovery service. Natural language search powered by SHV (Semantic Hybrid Vector) retrieval — combining keyword matching, structured field scoring, and semantic embedding similarit…
A2A agent · ARCASOS · 1 skill
Archivist AI Live MCP
Official remote MCP server for Archivist AI TTRPG campaign memory: characters, sessions, and more.
MCP server · io.github.Astrotomic
Ari Coach Live MCP
Second opinion on a hard decision from Ari, an AI with its own memory. Slow (2-4 min), paid.
MCP server · io.github.ariflixconomy
ASR Memory (에사 AI) — Shared memory for AI tools Live MCP
Shared memory for AI tools: save once, recall word for word from Claude, ChatGPT, Codex or Gemini.
MCP server · com.asrmemory
Assertion Memory Live MCP
Recall your team's coding-agent memory. Install the Assertion plugin to capture it automatically.
MCP server · io.github.Assertion-AI
Axon NeuroAutomata Live MCP
Protein analysis: ESM-2/ESMC embeddings, mutation scoring, landscape scans, ESMFold structure.
MCP server · ai.axonagentic
Brainiall Memory Live MCP
Persistent semantic memory storage, associative recall, and recent memory index by namespace.
MCP server · com.brainiall
Cairn.ink Memory Live MCP
Cross-session memory for AI agents with a Source Receipt for every memory, over MCP.
MCP server · ink.cairn
Capital Markets Agents: MCP+A2A Canada Live MCP
KYP Agentic Trading with the Capital Markets Knowledge Graph — eleven markets, in-country.
MCP server · io.github.allooloo

Related capabilities

Agent infrastructure Research AI models & inference x402 paid APIs Documents & PDFs Maps & travel Payments Web search

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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