
JapanFold
io.github.japanfoldPublished by GitHub account japanfoldv1.0.0Updated Oct 26, 2026
Fold proteins, co-fold ligands with binding affinity, design binders and embed sequences.
Overview
Remote MCP server for JapanFold that lets an assistant fold proteins, co-fold ligands with binding affinity, design binders and compute sequence embeddings.
- What you can do
- Fold protein sequences into structures with models such as Boltz-2, ESMFold-2, OpenFold3 and RoseTTAFold3
- Co-fold proteins with ligands and report binding affinity
- Design binders with BoltzGen, RFdiffusion3, PXDesign and related models, and score already-designed binders with AF2-IG
- Compute sequence embeddings with ESMC and SaProt
- List available model ids and their size limits, then submit asynchronous jobs and poll for results
- When to use it
- Useful when a conversation needs structural biology work — predicting protein structures, ligand binding, binder design or embeddings — without owning a GPU, and you want the assistant to run those jobs through a hosted API.
- Requirements
- A remote endpoint at api.japanfold.aiand.com/mcp; no local install or GPU. API access needs a JapanFold key from the account token page, sent as an Authorization Bearer header (JAPANFOLD_API_KEY for the skill or Claude Code setup). Connectors such as claude.ai, Claude Desktop and ChatGPT sign in instead of using a key.
Installation
In SourceWeft
- Open JapanFold in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.
Use with an agent
Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.
Read https://sourceweft.com/mcp/io.github.japanfold%2Fjapanfold/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.Other MCP clients
Add this to your client's mcpServers config.
{
"mcpServers": {
"japanfold": {
"type": "http",
"url": "https://api.japanfold.aiand.com/mcp"
}
}
}README
JapanFold skill
Fold proteins, co-fold with ligands (+ binding affinity), design binders, and
embed sequences from your AI agent, via the
JapanFold API. Get a key at
japanfold.aiand.com/account/token and set
JAPANFOLD_API_KEY.
No local GPU. Runs Boltz-2 / ESMFold-2 / OpenFold3 /
OpenBind-0 / RoseTTAFold3 / OpenDDE for structures, AF2-IG for scoring a binder you
already designed, BoltzGen / RFdiffusion3 /
PXDesign / RFD4-Proteina for design, and ESMC / SaProt for embeddings, on Tenstorrent.
Agents can call the API directly, no install needed:
Base URL https://api.japanfold.aiand.com, key in Authorization: Bearer.
GET /v1/models lists the model ids to send (boltz2, esmfold2, openfold3, ...)
with their size limits. The agent-readable summary is
llms.txt.
It's a single SKILL.md built on the open Agent Skills
standard, so it installs into any compatible harness with one command.
Install
One line installs it everywhere the open standard is supported: Claude Code, Cursor, Codex, Gemini CLI, Cline, Windsurf, Copilot, Amp and the rest:
- Target specific agents:
-a claude-code,-a cursor,-a codex,-a '*'(all). - Prefer not to use the installer? It is one file. Download it unchanged into
your agent's skills directory, for Claude Code:
curl -fsSL --create-dirs -o ~/.claude/skills/japanfold/SKILL.md https://japanfold.aiand.com/skill.md. A web-fetch tool returns only a summary of the page, so an agent should use curl too.
Claude Science manages skills in-app (no installer): Customize → Skills,
add from this repo (or paste SKILL.md) and publish it. Or skip install
entirely: the API is public and self-describing, so just ask:
"use the JapanFold API at api.japanfold.aiand.com to fold …".
Use
Once installed, ask your agent in plain language:
"Fold this sequence with Boltz-2 and report the confidence: MKTAYIAK…" "Design 10 nanobody binders against this target."
Or invoke it explicitly where supported: /japanfold.
MCP
The API is also a remote MCP server at https://api.japanfold.aiand.com/mcp, listed in the
MCP Registry as
io.github.japanfold/japanfold. claude.ai, Claude Desktop and ChatGPT add it as a connector and
sign in, no key needed. Claude Code:
claude mcp add --transport http japanfold https://api.japanfold.aiand.com/mcp --header "Authorization: Bearer $JAPANFOLD_API_KEY".
To publish a new registry version, bump version in server.json and run
mcp-publisher login github && mcp-publisher publish.
The API
https://api.japanfold.aiand.com: async (submit → poll → download), a key on every call.
Full contract at /v1/openapi.json.
See SKILL.md for endpoints, examples, and limits.
Fast mode is off unless the agent sends "params": {"fast": true}. It gives higher
throughput and may be slightly less accurate. The workbench turns it on for people clicking
through; the API and this skill leave it off so a scripted run gets the accurate path.
ESMFold-2 always runs fast on this hardware, and its job records fast: true.
Source: README.md at commit 0da945a
Tools
0Version history
1- v1.0.0LatestOct 19, 2026
Score
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