Vector MCP Server

MCP (Model Context Protocol) server for Vector - the Apex Fusion eUTXO L2. Enables AI agents (Claude, GPT, Gemini, or any MCP client) to interact with Vector natively: query balances, send transactions, deploy and interact with smart contracts, manage on-chain agent identities, and submit protocol improvement proposals.

Built on Ogmios + Koios - no Blockfrost dependency.

Vector mainnet is live. Full guides: Vector AI documentation.

Hosted servers - no install

Hosted instances run on both networks, exposing all 24 tools:

Network	Endpoint
Mainnet	https://mcp.vector.mainnet.apexfusion.org/sse
Testnet	https://mcp.vector.testnet.apexfusion.org/sse

Deployment status differs by network. Testnet auto-deploys from main on every merge, so it tracks this codebase closely. Mainnet stays on its last custodial image until a deliberate cutover deploy ships - that deploy is a separate, future step, not automatic and not implied by any merge (see docs/architecture/non-custodial-split.md, section 11, "Rollout"). Until it ships, treat the mainnet instance's signing tools as custodial: assume they may still accept a mnemonic as a tool-call parameter, and prefer self-hosting this release or the testnet instance instead.

Connect from Claude Code in one command:

claude mcp add --transport sse vector-mcp https://mcp.vector.mainnet.apexfusion.org/sse

Security notice: as of this release, the non-custodial migration is complete in this codebase. No tool in this repository accepts a mnemonic, private key, or any other key material. Every build_* tool constructs an unsigned transaction from a wallet address only, and every signing operation happens locally on your own machine, through the local signer companion. Broadcast the signed result with vector_submit_transaction - your seed phrase never leaves your machine, and no server running this release ever holds one. This is enforced mechanically in the code, not just by convention: the builder's custody boundary test scans every source file for key-material vocabulary against an allowlist that is now empty and pinned at size zero, so a future change cannot silently reintroduce a mnemonic parameter without failing that test by name. This is a claim about the code, not about every deployment of it - see the deployment status note above the connect command, and docs/architecture/non-custodial-split.md for the full rollout plan.

Self-hosting instructions are below.

Local signer (non-custodial path)

packages/signer is a local MCP server that holds your key and signs transactions locally instead of handing your mnemonic to a shared host. It has no network access at all — stdio transport, no Provider, no egress — so a key given to it never reaches a shared server or your model provider. Four tools: vector_signer_get_address, vector_signer_decode_transaction, vector_signer_sign, vector_signer_get_spend_limits.

In this codebase, this signer is the single signing point for every family the builder exposes. The full non-custodial flow is live in this release for all of them: vector_signer_get_address → build_* → vector_signer_sign → vector_submit_transaction → vector_await_transaction. No step in that chain puts a mnemonic in front of a server running this code, or your model provider, for any tool. The build → submit → await half is E2E-proven on Vector testnet across the wallet/tx, smart-contract, agent-registry, and self-improvement families, including the first keyless-built proposal submission the deployed self-improvement module validator has ever accepted; see packages/signer/README.md for exactly what that testing does and does not exercise on the signer's side. This describes the code, not every deployment of it - see the deployment status note above.

See packages/signer/README.md for configuration, tools, and known limitations.

Features

• Wallet & queries - balances, UTxOs, and transaction history for any address (no key material)
• Keyless transaction building - build unsigned AP3X/token/multi-output transactions and contract interactions; sign locally, broadcast via submit
• Smart contracts - deploy Plutus/Aiken validators, lock and spend UTxOs at script addresses (keyless)
• Agent registry - register, discover, update, transfer, and deregister on-chain AI agent identities via soulbound NFTs (keyless - build, sign locally, broadcast)
• Agent messaging - send on-chain messages between agents via TX metadata (keyless)
• Self-Improvement Module - browse, submit, critique, and endorse improvement proposals; the on-chain module is live on Vector mainnet, and every write tool is keyless in this codebase
• Safety controls - per-identity rate limiting; spend limits for every family are enforced by the local signer, per user - the server holds no spend-limit state of its own
• SSE transport - HTTP server with Server-Sent Events for MCP client connectivity

MCP Tools (24)

Wallet & Queries

Tool	Description
vector_get_balance	Get AP3X and token balances for any address
vector_get_utxos	List UTxOs for an address
vector_get_transaction_history	Get transaction history for an address

Transactions

Tool	Description
vector_build_send_apex	Build an unsigned AP3X payment (keyless — sign with the local signer)
vector_build_send_tokens	Build an unsigned native-token transfer (keyless)
vector_build_transaction	Build an unsigned multi-output transaction (keyless, never submits)
vector_dry_run	Simulate a transaction without submitting - estimate fees and validate
vector_submit_transaction	Broadcast an already-signed transaction (for example one signed by the local signer)
vector_await_transaction	Wait for a submitted transaction to be confirmed on-chain

Smart Contracts

Tool	Description
vector_build_deploy_contract	Build an unsigned deployment of a Plutus V1/V2/V3 or Aiken validator (keyless)
vector_build_interact_contract	Build an unsigned lock or spend at a script address, with a redeemer (keyless)

Agent Registry

Tool	Description
vector_build_register_agent	Build an unsigned agent registration - mints a soulbound identity NFT and locks a 10 AP3X deposit (keyless)
vector_discover_agents	Discover registered agents, filter by capability or framework (no wallet needed)
vector_get_agent_profile	Get an agent's full profile by DID (no wallet needed)
vector_build_update_agent	Build an unsigned update to an agent's name, description, capabilities, framework, or endpoint (keyless)
vector_build_transfer_agent	Build an unsigned transfer of agent ownership to a new address (keyless)
vector_build_deregister_agent	Build an unsigned deregistration - burns the identity NFT and returns the 10 AP3X deposit (keyless)
vector_build_message_agent	Build an unsigned on-chain message to an agent via TX metadata (label 674) (keyless)

Self-Improvement Module

Tool	Description
vector_self_improvement_browse	Browse improvement proposals, critiques, and endorsements
vector_self_improvement_analyze_metrics	Proposal metrics: activity, adoption rate, treasury health, engagement
vector_build_self_improvement_proposal_lock	Build an unsigned proposal-stake lock (step 1 of 2, keyless)
vector_build_self_improvement_proposal_spend	Build an unsigned proposal submission - spends the lock and mints the proposal and activity tokens (step 2 of 2, keyless). Two transactions, agent-orchestrated.
vector_build_self_improvement_critique	Build an unsigned critique on a proposal - support, oppose, or propose amendments (keyless)
vector_build_self_improvement_endorse	Build an unsigned endorsement of a proposal by staking AP3X (keyless)

Agent DIDs follow the format: did:vector:agent:{policyId}:{nftAssetName}

Example non-custodial flow for a registry op: vector_build_register_agent → vector_signer_sign → vector_submit_transaction → vector_await_transaction.

Self-hosting

1. Install and build

npm install
npm run build

2. Configure environment (optional)

cp .env.example .env
# Edit .env with your endpoint URLs (defaults point to Vector testnet; mainnet URLs below)

Every build_* tool is keyless: it takes a wallet address, never a mnemonic. No tool call against this server ever needs a mnemonic parameter, for any family - see the security notice above.

3. Run

npm start
# Server listens on port 3000 (configurable via PORT env var)

If this instance will be reachable by anyone but you, set MCP_AUTH_TOKENS first - see Configuration below.

4. Add to Claude Desktop

Add to your Claude Desktop MCP config (claude_desktop_config.json):

{
  "mcpServers": {
    "vector": {
      "command": "node",
      "args": ["/path/to/vector-mcp-server/packages/builder/build/index.js"],
      "env": {
        "VECTOR_OGMIOS_URL": "https://ogmios.vector.testnet.apexfusion.org",
        "VECTOR_SUBMIT_URL": "https://submit.vector.testnet.apexfusion.org/api/submit/tx",
        "VECTOR_KOIOS_URL": "https://koios.vector.testnet.apexfusion.org/",
        "VECTOR_EXPLORER_URL": "https://vector.testnet.apexscan.org"
      }
    }
  }
}

For mainnet, use the mainnet endpoint table below. (No local setup needed if you use the hosted servers above.)

Docker

npm run build
docker build -t vector-mcp .
docker run -p 3000:3000 vector-mcp

If this instance will be reachable by anyone but you, set MCP_AUTH_TOKENS first - see Configuration below (docker-compose.yml in this repo binds 127.0.0.1 by default; the command above does not).

Configuration

Variable	Description	Default
PORT	HTTP server port	3000
VECTOR_OGMIOS_URL	Ogmios HTTP JSON-RPC endpoint	https://ogmios.vector.testnet.apexfusion.org
VECTOR_KOIOS_URL	Koios REST API endpoint	https://v2.koios.vector.testnet.apexfusion.org/
VECTOR_SUBMIT_URL	Transaction submit API	https://submit.vector.testnet.apexfusion.org/api/submit/tx
VECTOR_EXPLORER_URL	Block explorer base URL	https://vector.testnet.apexscan.org
VECTOR_RATE_LIMIT_PER_MINUTE	Max tool calls per minute	60
MCP_AUTH_TOKENS	Bearer tokens that may call this server. Comma-separated; each entry is label:token or a bare token. When unset, the server is open to anyone who can reach it.	(unset — auth disabled)

This server has no spend-limit or audit-log configuration of its own: it holds no key material for any family, so it has nothing left to limit. Every spend limit, and the audit log recording it, lives in your local signer instead - see VECTOR_SIGNER_SPEND_LIMIT_PER_TX / VECTOR_SIGNER_SPEND_LIMIT_DAILY / VECTOR_SIGNER_AUDIT_LOG_PATH in packages/signer/README.md.

Running a public instance? Set MCP_AUTH_TOKENS. Without it every caller is treated as one anonymous identity and shares a single rate-limit bucket, so one busy client throttles everyone. Rate limits are applied per identity, so give each client its own token.

Malformed values fail loudly, not silently. The server refuses to start if MCP_AUTH_TOKENS contains an empty token, a token with embedded whitespace, a duplicate token, or a value where every comma-separated entry is blank (e.g. a stray ,,,) — each raises a startup error that names the problem but never echoes a token value. Commas delimit entries and cannot be escaped, so generate tokens from a comma-free charset (hex / base64url / alphanumeric).

Mainnet endpoints

Variable	Mainnet value
VECTOR_OGMIOS_URL	https://ogmios.vector.mainnet.apexfusion.org
VECTOR_SUBMIT_URL	https://submit.vector.mainnet.apexfusion.org/api/submit/tx
VECTOR_KOIOS_URL	https://v2.koios.vector.mainnet.apexfusion.org/
VECTOR_EXPLORER_URL	https://vector.apexscan.org/en/

Testing

npm run test:unit

No wallet, no network — pure logic only (CBOR encode/decode assertions).

npm run test:smoke

Builds the server, boots it, and asserts the exposed tool inventory matches the checked-in snapshot. No wallet, no external network. CI runs this and test:unit on every PR.

echo "your mnemonic words here" > packages/builder/mnemonic.txt
npm run test:integration

Requires mnemonic.txt in packages/builder/ containing a funded Vector testnet mnemonic. Covers the core tools end-to-end against Vector testnet, including the full agent lifecycle: register, discover, profile, update, transfer, message, and deregister (all keyless now: build → sign → submit → await per step). Also runs keyless-build.test.ts, registry-keyless.test.ts, and self-improvement-keyless.test.ts - tier-1 suites needing no mnemonic at all, each building unsigned transactions against live public data only (vector_build_send_tokens is covered offline, by unit tests and the legacy suite above; self-improvement-keyless.test.ts covers critique, endorse, and proposal-lock builds, plus a not-found rejection path on proposal-spend). Set VECTOR_E2E_SUBMIT=1 to additionally run each family's gated end-to-end suite, fully on-chain: keyless-e2e.test.ts lands one real self-send (~0.16 AP3X fee); registry-e2e.test.ts runs a full register → update → deregister agent lifecycle (the 10 AP3X deposit round-tripped exactly, fees only as net cost); self-improvement-e2e.test.ts locks and spends a real improvement proposal through the deployed module validator, then critiques and endorses it (≈48 AP3X in stakes and module minimums, plus six transaction fees, one-way - the stakes are locked by the module's own design, not lost). Set LEGACY_FULL=1 to additionally exercise the same self-improvement lock → spend sequence inside run.test.ts itself (off by default, since self-improvement-e2e.test.ts already proves that exact path). Never runs in CI.

npm run test:smoke:signer

Builds the local signer (packages/signer), boots it over stdio, and exercises all four of its tools, including the fail-closed audit-write-failure path. No wallet, no network. CI runs this on every PR alongside the two smoke tests above.

export VECTOR_SIGNER_MNEMONIC_FILE=/absolute/path/to/testnet-mnemonic.txt
npm run test:integration:signer

Requires a funded Vector testnet wallet. Builds a real unsigned transaction the way the hosted builder does (no key), then has the local signer decode, policy-check, and sign it against live chain data. Never submits. Never runs in CI. See packages/signer/README.md.

Architecture

┌──────────────────────┐      ┌──────────────────────────┐
│  Claude / GPT / etc. │◄────►│  vector-mcp-server       │
│  (any MCP client)    │ SSE  │                          │
└──────────────────────┘      │  ┌────────────────────┐  │
                              │  │ Rate Limiter        │  │
                              │  │ (60 calls/min)      │  │
                              │  └────────┬───────────┘  │
                              │           │               │
                              │  ┌────────▼───────────┐  │
                              │  │ Lucid + Ogmios     │  │
                              │  │ Provider            │  │
                              │  └────────┬───────────┘  │
                              │           │               │
                              │  ┌────────▼───────────┐  │
                              │  │ Ogmios / Koios /   │  │
                              │  │ Submit API          │  │
                              │  └────────────────────┘  │
                              └──────────────────────────┘

No safety layer sits between the rate limiter and the provider: this server holds no key material for any family, so it has no spend limits of its own left to enforce. Every spend limit lives in your local signer instead.

About Vector

Vector is Apex Fusion's eUTXO L2, running Cardano mainnet parameters (Conway era, Plutus V3). Sub-1-second optimistic finality and deterministic fees make it a natural chain for AI agent workloads. Mainnet is live.

• Docs: https://apex-fusion.github.io/vector-ai-documentation/
• Explorer (mainnet): https://vector.apexscan.org/en/
• Explorer (testnet): https://vector.testnet.apexscan.org
• Apex Fusion: https://apexfusion.org