avalanche-mcp-server

Install

Hosted — nothing to install. Same shape as Ava Labs' build.avax.network/api/mcp: a public Streamable HTTP endpoint, no API key.

claude mcp add avalanche --transport http https://avalanche-mcp.dev/mcp

Run /mcp in Claude Code to verify — you should see avalanche · 41 tools.

Related MCP server: Somnia MCP Server

What it does

Ask in plain language; the agent picks the tools and cites its sources.

› What changes in the Helicon upgrade for my C-Chain indexer?

⏺ avax_upgrade_lookup(query: "Helicon")
⏺ avax_acp_lookup(query: "ACP-194")
⏺ avax_get_doc(content/docs/primary-network/helicon-upgrade.mdx)

Helicon (AvalancheGo v1.15.0-fuji) is live on Fuji since 2026-07-28; mainnet is not
scheduled yet. ACP-194 Continuous Execution decouples consensus from execution, so a
block's state root settles after a τ delay (~5 s) — don't treat "latest" as executed
state. ACP-283 makes the minimum gas price dynamic, so never hardcode a fee floor.

Sources: build.avax.network/docs/primary-network/helicon-upgrade
         build.avax.network/docs/acps/194-continuous-execution

Other things to ask on day one:

• "Plan a permissioned enterprise L1 on Fuji with five validators, then generate the genesis."

• "Explain the NativeMinter precompile and how to enable it after launch with upgrade.json."

• "Send a message from Fuji C-Chain to Dispatch with Teleporter, with relayer setup."

• "Which ACPs are activated, and what does ACP-176 change about gas?"

• "My CLI says subnet not tracked when I hit the RPC. What's wrong?"

Capabilities

41 tools, every one read-only. Nothing signs or broadcasts transactions.

Plus MCP resources (avax://docs/{path}, avax://guides/{name}, avax://networks) and prompts (avalanche_launch_l1, avalanche_deploy_contract, avalanche_icm_bridge, avalanche_learn). The full tool list is at avalanche-mcp.dev/#tools or via tools/list.

Verified, not guessed

Facts that models commonly get wrong are pinned in code and checked against the docs: the C-Chain minimum base fee is 1 wei since Fortuna (ACP-176), not 25 nAVAX; subnet-evm and icm-contracts now live in avalanchego/graft and icm-services; Helicon is Fuji-only as of August 2026. Every answer carries the build.avax.network or GitHub URL it came from.

Knowledge sources

The index is built by npm run build-index from official repositories and ships inside the package, so the first search works offline:

avax_list_topics reports the index build date so the agent knows how fresh it is; avax_fetch_live_doc fetches the current version of any page when that matters. Credential-shaped strings in documentation examples are redacted at build time.

Configuration

No configuration is required. Optional environment variables (local mode):

Self-hosting

Run the HTTP transport anywhere Node runs:

npx -y avalanche-mcp-server --http        # POST http://localhost:3333/mcp  (PORT to change)

Or mount it in any web-standard runtime — Next.js route handlers, Cloudflare Workers, Hono:

import { handleMcpRequest } from "avalanche-mcp-server";
export const POST = (req: Request) => handleMcpRequest(req);

This is exactly how avalanche-mcp.dev serves it (source). Responses are stateless JSON with CORS open, so browser-based clients work too.

Works with the official Avalanche MCPs

Ava Labs' hosted MCP is always current for Builder Hub search, CLI / RPC lookup and runbooks; this server adds offline knowledge, structured ACPs and upgrades, live EVM tools and end-to-end workflows. They compose:

claude mcp add avalanche          --transport http https://avalanche-mcp.dev/mcp
claude mcp add avalanche-hosted   --transport http https://build.avax.network/api/mcp
claude mcp add avalanche-chainkit -- npx -y @avalanche-sdk/chainkit mcp-server
claude mcp add avalanche-avacloud -- npx -y @avalabs/avacloud-sdk mcp-server --apikey $AVACLOUD_API_KEY

avax_hosted_call already proxies the hosted server from inside this one, so a single registration covers most setups.

Development

git clone https://github.com/Eelvanpsd/Avalanche-mcp.git && cd Avalanche-mcp
npm install && npm run build       # the index ships in the repo
npm run dev                        # stdio server via tsx
npm run inspect                    # MCP Inspector UI
npx tsx scripts/smoke.ts           # end-to-end tool check over stdio
REFRESH=1 npm run build-index      # re-download sources and rebuild the index

Extending it is one file each: curated guides in src/knowledge/guides.ts, the network registry in src/config/networks.ts, upgrade timeline in src/knowledge/upgrades.ts, new sources in scripts/build-index.ts.

License

MIT. Avalanche MCP is an independent, community-built project and is not affiliated with or endorsed by Ava Labs or the Avalanche Foundation. Avalanche and the Avalanche mark are trademarks of their respective owners.