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

| Client | Configuration | |---|---| | Claude Code | Command above, or commit .mcp.json: { "mcpServers": { "avalanche": { "type": "http", "url": "https://avalanche-mcp.dev/mcp" } } } | | Cursor / Windsurf | { "mcpServers": { "avalanche": { "url": "https://avalanche-mcp.dev/mcp" } } } | | Claude Desktop | { "mcpServers": { "avalanche": { "command": "npx", "args": ["-y", "mcp-remote", "https://avalanche-mcp.dev/mcp"] } } } | | Local / offline | claude mcp add avalanche -- npx -y avalanche-mcp-server — runs on your machine over stdio, no rate limits | | Any HTTP client | curl -X POST https://avalanche-mcp.dev/mcp -H 'content-type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' |

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

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?"
• "Chart C-Chain active addresses for the last 90 days, and which L1s have the most bot traffic?"

Capabilities

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

| Area | Tools | What you get | |---|---|---| | Knowledge | 7 | Full-text search over a bundled index of build.avax.network (docs, Academy, 234 integrations, blog), Subnet-EVM precompile docs, ICM contracts, Avalanche CLI reference — 9.9k chunks, every hit with its source URL. Curated guides for architecture, L1 launch, precompiles, ICM, gas and troubleshooting. | | Protocol & upgrades | 4 | All 36 ACPs with structured status / track / authors; the Banff → Helicon upgrade timeline with dates, versions and developer impact; live ACP signaling from nodes. | | Workflows | 6 | Tailored L1 launch plans, valid genesis.json with the right precompiles, Teleporter sender/receiver recipes with real addresses, error triage, Builder Console deep links and platform-cli commands. | | Live EVM | 8 | C-Chain, Fuji, known L1s or any RPC URL: balances, blocks, receipts, eth_call, gas estimation. | | P-Chain · X-Chain · node | 8 | Validators, subnets and L1s, staking economics, tx status, UTXO balances, node and network info. | | Avalanche Data API | 5 | Indexed chains, ERC-20 balances, transaction history, token metadata, L1 validators. | | Network stats | 4 | C-Chain metric time series (transactions, active addresses/senders, fees, gas, TPS, cumulative addresses/contracts/deployers), Primary Network staking history since 2020, a 30-day ranking of every Avalanche L1 with market share, concentration and estimated bot-traffic share, and an SVG chart + table renderer so stats show up as UI. Backed by SOCI4L's public API (a daily snapshot of the Ava Labs Metrics API, P-Chain cross-checked). | | Hosted federation | 3 | Proxy to Ava Labs' official MCP for build_plan runbooks, CLI / RPC lookup and always-fresh search. |

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:

| Source | Content | |---|---| | ava-labs/builders-hub | docs, Academy (L1 and blockchain tracks), integrations, blog | | avalanche-foundation/ACPs | every ACP README, parsed into structured metadata | | ava-labs/avalanchego | README, docs/, RELEASES, graft/subnet-evm precompile and plugin docs | | ava-labs/icm-services | Teleporter / ICTT contracts, relayer, signature aggregator | | ava-labs/avalanche-cli, ava-labs/avalanche-starter-kit | command reference, templates | | soci4l.net/api/avalanche (live) | C-Chain metrics, L1 rankings, staking series — SOCI4L_API_URL overrides the base |

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):

| Variable | Purpose | |---|---| | AVAX_DATA_API_KEY | Higher rate limits for the Avalanche Data API tools. Free key at build.avax.network. (GLACIER_API_KEY is accepted as a legacy alias.) | | AVAX_DATA_API_URL | Override the Data API base URL | | AVAX_HOSTED_MCP_URL | Override the hosted Avalanche MCP endpoint used by avax_hosted_* | | AVAX_ALLOW_CUSTOM_RPC | false disables arbitrary RPC URLs in the network argument (built-in chains + AVAX_RPC_ALLOWLIST only). Set this on any public/hosted deployment — the default (true, for local use) still blocks loopback / private / link-local / metadata targets. | | AVAX_RPC_ALLOWLIST | Comma-separated extra RPC hostnames to allow when custom RPCs are disabled | | AVAX_HOSTED_RATE_LIMIT | Max avax_hosted_call requests per minute (default 40, under the hosted 60/min budget) |

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.

Security

Every tool is read-only — the server never holds a private key, signs, or broadcasts. Additional hardening for public deployments:

• SSRF protection — the network argument may be a raw RPC URL, which the server fetches. Loopback, private, link-local and cloud-metadata targets are always refused; set AVAX_ALLOW_CUSTOM_RPC=false to allow only built-in chains (recommended when exposing the HTTP endpoint publicly).
• Rate limiting — the server throttles its own calls to Ava Labs' hosted MCP to stay under the shared 60/min budget. The HTTP endpoint itself is unauthenticated, so put a per-IP rate limiter in front (the reference deployment ships one; Upstash Ratelimit is a good managed option).
• Input validation — addresses and identifiers are validated with zod/viem before any upstream request.

Report vulnerabilities via a private GitHub security advisory on the repo.

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.