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:

Deployment status: both networks are current. Both hosted instances run today's completed migration: testnet since the 2026-07-31 morning merges (auto-deployed from main), mainnet since a deliberate cutover deploy the same day (see docs/architecture/non-custodial-split.md, section 11, "Rollout", for the full history). Both hosted instances are open access - no bearer token is required to connect. Callers are admitted anonymously with per-IP rate limiting. That is an access-control property, and it is separate from custody: neither instance accepts a mnemonic from any caller, with or without a token. Self-hosted deployments can still gate access with MCP_AUTH_TOKENS - see Configuration.

Transport: Streamable HTTP only, as of 2.0.0. The legacy SSE pair (/sse + /messages), deprecated by the MCP spec (2026-07-28 revision), was removed in this release - those paths now answer 404. Every client connects to /mcp, the endpoint the table above lists. This is a breaking change for SSE clients: reconnect with --transport http and the /mcp URL (below). The server also answers any-origin CORS (browser MCP clients are first-class callers) and exposes an unauthenticated GET /health liveness probe. This describes the code - each hosted instance serves it once this release deploys there (testnet automatically on push to main, mainnet on a deliberate cutover dispatch).

Connect from Claude Code in one command. No token needed for the hosted instances.

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

Swap in the testnet host to connect to testnet instead. Self-hosting (below) gives every caller open access to your own instance unless you set MCP_AUTH_TOKENS.

Security notice: the non-custodial migration is complete, in this codebase and on both hosted instances, as of the 2026-07-31 cutover deploy. 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 describes this release and the 2026-07-31 deploy specifically - a later deploy is a separate operational action, not automatically covered by this notice; see the deployment status note above and docs/architecture/non-custodial-split.md for the full rollout history.

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 only, 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
• Streamable HTTP transport - the modern MCP transport at /mcp, with any-origin CORS for browser clients and an unauthenticated GET /health probe (the legacy SSE pair was removed in 2.0.0)

MCP Tools (24)

Wallet & Queries

Transactions

Smart Contracts

Agent Registry

Self-Improvement Module

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