bagos-mcp-server

BagOS 🚦

An MCP server that lets an AI assistant trade on Solana — and signs nothing until you say so.

🚀 Install

npx bagos-mcp-server

Claude Desktop — ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "bagos": {
      "command": "npx",
      "args": ["-y", "bagos-mcp-server"],
      "env": {
        "BAGS_API_KEY": "your-key-here"
      }
    }
  }
}

Claude Code:

claude mcp add bagos --env BAGS_API_KEY=your-key-here -- npx -y bagos-mcp-server

Restart the client, then ask it: "check the bagos heartbeat". The server prints a configuration report to stderr on startup; if something is missing it tells you which variable and why. A key alone gives you the 11 read tools — writes stay off until you configure them (Getting Started).

🔒 Why this is safe to hand an assistant

• Nothing signs on the first call. A write tool answers with a preview and a single-use token fingerprinted to those exact arguments; nothing reaches the chain until you call again with it.
• Hard SOL caps. 0.1 per transaction and 1 per session by default, refused before the Bags SDK is called.
• Devnet by default. Writes are mainnet-only, so an unconfigured install cannot spend real money.

Full threat model, disclosure policy and the limits of each control: .github/SECURITY.md.

⚠️ If you used 1.x — v2.0.0 corrected a serious defect

v2.0.0 corrects a serious defect. In 1.x the write tools built transactions, discarded them, and reported success — nothing was ever signed or submitted. If you used 1.x and believed a trade or claim executed, it did not. See CHANGELOG.md.

2.x is live on npm and is what npx bagos-mcp-server installs — see the latest release. Every release ships with npm provenance — the tarball is cryptographically attested to this repository and the commit that built it. 1.x is deprecated on npm. If you are still on it, upgrade.

📦 Where it's listed

💡 The Problem & Solution

The Problem

An MCP server that can move money gives an AI assistant a signing key. The assistant decides, and the transaction is already on chain by the time a human reads about it. Nothing in the protocol makes the model pause, and nothing bounds what a single misunderstood instruction can spend.

The Solution

BagOS lets an AI assistant read Bags/Solana token data and — with explicit confirmation — execute swaps and claim creator fees from your wallet. Writes are off unless you configure them, they are mainnet-only, and the first call to a write tool signs nothing: it returns a preview and a single-use token that only authorizes the exact arguments it was issued for.

🏗️ Architecture & Tech Stack

Every write goes through this:

token gate → spend caps → confirmation → simulate → sign → send → confirm

Tool	Type	What it does
bags_heartbeat	read	Server status and wallet reachability
bags_get_token_analytics	read	Lifetime fee data for a token mint
bags_get_creators	read	Top token creators by lifetime fees
bags_get_trade_quote	read	Price quote for a swap. Does not trade.
bags_get_claimable_fees	read	Fees currently claimable by your wallet
bags_get_partner_stats	read	Partner config claim statistics
bags_get_token_claim_stats	read	Per-creator claim totals — the royalty roster with amounts claimed
bags_get_token_claim_events	read	The claim audit trail for a token, paginated
bags_get_token_creators	read	Who shares a token's fees, and in what proportion
bags_resolve_launch_wallet	read	Social handle (twitter/tiktok/kick/github) → fee-share wallet
bags_authenticate	read	Verify wallet ownership via Ed25519 signature
bags_prepare_token_metadata	gated	Creates token info + metadata. Does not launch a token.
bags_execute_trade	write	Swap tokens. Signs and submits.
bags_claim_fees	write	Claim creator/LP fees. Signs and submits.

bags_prepare_token_metadata reserves a mint and uploads metadata. Completing a launch also requires a Meteora fee-share config, whose fee-claimer split has to be your decision — so this server does not implement that step rather than guessing at it. Finish the launch at bags.fm.

🔐 Write Tools & Spend Controls

Writes are off unless you configure them, and they are mainnet-only.

Bags has no devnet deployment. Its API endpoint and its Meteora/fee-share program IDs are all mainnet. This server nonetheless defaults to devnet, so an unconfigured install cannot spend real money. Calling a write tool on devnet returns an explanation, not a cryptic program error.

The first call to a write tool signs nothing. It returns a preview and a single-use token:

⚠️  CONFIRMATION REQUIRED — nothing has been signed or sent.

Action:  Swap 0.05 of So1111…1112
         for       EkJuyY…dBAGS
         expect    4823917722 (min 4679199990)
         slippage  3%
         network   🔴 MAINNET — real funds

Spend:   0.05 SOL
Caps:    0.1 SOL/tx · 0/1 SOL used this session

To execute, call bags_execute_trade again with the identical arguments plus:
  confirm: "kR3nT9xQm2vP"

The token is a fingerprint of the tool name plus the exact arguments, so one issued for a 0.01 SOL swap cannot authorize a 10 SOL one. It expires in five minutes and is consumed on every outcome, so it cannot be replayed.

On success you get a real signature and explorer link — never a success message for a transaction that did not land.

Set BAGS_ALLOW_UNCONFIRMED=true to skip the preview. Spend caps still apply.

The caps only bind on SOL. A swap whose input is some other token cannot be valued in SOL, so no cap can limit it. Those swaps are refused by default; set BAGS_ALLOW_UNCAPPED_TOKEN_SWAPS=true to permit them, and the preview will say plainly that the trade is uncapped.

📊 Engineering Rigor

337 tests. The bypass tests around the spend caps and the confirmation step are load-bearing; treat a change there as a security change. They are mutation- checked: removing the cap guard, the confirmation check, the decimals lookup, or the spend recorder each makes the suite fail.

Layer	Status	Details
Real default path	✅	No kill-switch flag in any documented command. USE_MOCK_DATA defaults off; when on, it affects only the bags_get_claimable_fees tool, stamping ⚠️ [MOCK DATA ENABLED] on that tool's own response. The other 13 tools ignore it. Live-run receipts in DEMO.md
Code quality	✅	ESLint + tsc --noEmit, both clean
Unit testing	✅	Jest, 337 tests / 17 suites, 100% statements · branches · functions · lines, enforced
High-signal tests	✅	Mutation-checked cap/confirmation bypass tests · a leak-channel regression test (the API key used to be echoed into tool output) · network-mismatch refusal
Security	✅	CodeQL SAST · Dependabot SCA · gitleaks over full history (fetch-depth: 0) · secret scanning + push protection on · npm audit in CI as a ratchet — see below
Dependency debt	⚠️	6 advisories, 0 critical — down from 90. Everything patchable was cleared with version-scoped overrides (see package.json). The 6 that remain are one root cause, bigint-buffer GHSA-3gc7-fjrx-p6mg, counted once at each level of the chain it travels up to @bagsfm/bags-sdk. No patched bigint-buffer exists — 1.1.5 is the installed version, the latest version, and vulnerable. CI blocks any critical and any increase over .audit-baseline.json. Note: npm honours overrides only in a root project, so these protect this repo and CI, not consumers of the published package.
CI	✅	4 stages (Quality → Security ∥ Test → Build) with cancel-in-progress concurrency; Node 22 + 24 matrix; packaged-artifact and entrypoint checks
CD	✅	Release → tarball audit → npm publish --provenance → deprecate the superseded version. A second workflow submits server.json to the MCP registry via OIDC. Both gated on the full CI suite. 1.0.0 is deprecated on npm with a pointer to the defect it carried.
On-chain proof	✅	npm run proof:devnet lands a real transaction through the production write path and re-fetches it from the chain. Captured 2026-08-16: 2kvu25xW…U5Dm, slot 484219564, err: null. Anyone can re-verify it — see DEMO.md
Community standards	✅	Code of Conduct · Contributing · Security policy · issue + PR templates

E2E browser tests and Lighthouse budgets are deliberately absent: this is a stdio/HTTP MCP server with no web UI, so both would measure nothing. The equivalent end-to-end coverage is npm run demo, which drives all read tools over real MCP JSON-RPC against the live API.

🚀 Getting Started

Prerequisites

You need a Bags API key from dev.bags.fm. That alone enables the read-only tools. For trading and fee claims you also need a Solana keypair file and the gating token — see Write Tools & Spend Controls.

Enabling writes

Writes stay off until all of these are set:

{
  "mcpServers": {
    "bagos": {
      "command": "npx",
      "args": ["-y", "bagos-mcp-server"],
      "env": {
        "BAGS_API_KEY": "your-key-here",
        "BAGS_NETWORK": "mainnet",
        "BAGS_KEYPAIR_PATH": "~/.config/bags/keypair.json",
        "BOS_TOKEN_MINT": "EkJuyYyD3to61CHVPJn6wHb7xANxvqApnVJ4o2SdBAGS",
        "BAGS_MAX_SOL_PER_TX": "0.1",
        "BAGS_MAX_SOL_PER_SESSION": "1.0"
      }
    }
  }
}

Configuration

Variable	Required	Default	Notes
BAGS_API_KEY	yes	—	From dev.bags.fm
BAGS_NETWORK	no	devnet	devnet or mainnet. Writes need mainnet.
SOLANA_RPC_URL	no	public cluster RPC	Must agree with BAGS_NETWORK or the server refuses to start
BAGS_KEYPAIR_PATH	writes only	~/.config/bags/keypair.json	JSON byte-array keypair file
BOS_TOKEN_MINT	writes only	—	Gating token mint
BOS_REQUIRED_BALANCE	no	10000	Minimum gating-token balance. 0 disables the gate (any balance passes); a non-numeric value is refused at startup rather than silently defaulting.
BAGS_MAX_SOL_PER_TX	no	0.1	Per-transaction spend cap
BAGS_MAX_SOL_PER_SESSION	no	1.0	Per-process spend cap
BAGS_ALLOW_UNCONFIRMED	no	false	Skip the confirmation step
BAGS_ALLOW_UNCAPPED_TOKEN_SWAPS	no	false	Permit swaps whose input is not SOL. The caps are SOL-denominated and cannot limit these.

🧪 Testing & CI

npm ci
npm run ci            # lint + typecheck + tests with coverage
npm run dev           # stdio server with watch
npm run inspector     # MCP Inspector against the built server
npm run proof:devnet  # land a real devnet transaction through the write path

proof:devnet uses a persisted throwaway keypair (.proof/, gitignored), funds it from the devnet faucet when needed, and pushes a transfer through the same simulate/sign/send/confirm path the write tools use — then re-fetches the signature from the chain instead of trusting the function's return value. That last step is the whole point: a function returning success is a claim, and a signature you can open on an explorer is evidence.

📽️ Demo Materials

• DEMO.md — receipts from a real run against the live Bags mainnet API: 7 scenarios, 8 steps, per-step latency, plus the network-mismatch guard and the token gate caught refusing a write.
• docs/examples.md — prompts you can type at your assistant and what each should do.
• docs/KNOWN_ISSUES.md — what is currently broken and why, including what has already been ruled out. Open advisories are explained there rather than left for you to discover.

🛡️ Security

Read SECURITY.md before pointing a funded wallet at this.

Summary: your private key is read from disk, used to sign, and never logged, never sent anywhere, and never placed in an error message. Tool errors return a message only — no stack traces — with key-shaped strings redacted. The startup report strips credentials from the RPC URL. If the RPC endpoint's cluster disagrees with BAGS_NETWORK, the server refuses to start rather than sign mainnet transactions under a devnet banner.

The same rule now covers the Bags API key: bags_authenticate writes it to ~/.config/bags/credentials.json and echoes only a four-character tail. It used to print the key in full, which published a live credential into the assistant's context and every transcript downstream of it. If you ran bags_authenticate on a version before this change, rotate that key at dev.bags.fm.

Report vulnerabilities via GitHub security advisories.

📄 License

MIT — see LICENSE.