MCP server Kalshi Kernel

Kalshi Kernel

An unofficial, safety-focused Model Context Protocol (MCP) server for Kalshi event contracts and perpetual markets. This is a pre-release project that is not ready for trading. The server is designed for agent harnesses such as Hermes and exposes a deliberately small tool surface generated from Kalshi's published API contracts.

Canonical publisher: CopyleftDev. Planned source and container releases use github.com/copyleftdev/kalshi-kernel and ghcr.io/copyleftdev/kalshi-kernel respectively.

[!CAUTION] Pre-release software that can submit real orders. Published tags are conformance-tested scaffolds; the current main branch adds market-data, paper-trading, and live event-contract adapters. Configured live mode can place, amend, and cancel real orders. Review the exact commit, configuration, tests, and limits before running it with credentials; do not infer readiness from the version string.

[!IMPORTANT] This community project is not an official Kalshi product and is not affiliated with, endorsed by, sponsored by, or supported by KalshiEX LLC or its affiliates. “Kalshi” is used only to identify interoperability with Kalshi's published APIs.

The independent Kernel mark follows a conservative interpretation of Kalshi's published color, contrast, clear-space, and misuse guidance. It does not use or modify Kalshi's logo. See the visual identity usage rules.

Why this project exists

Trading APIs are broad and optimized for application developers. Agents need a narrower boundary with explicit intent, strict schemas, predictable errors, and strong separation between simulation and real-money execution. Kalshi Kernel provides that boundary while continuously testing its generated clients against the latest upstream contracts.

The design priorities are:

• paper mode by default;
• immutable execution mode for the lifetime of a process;
• explicit acknowledgement and credentials before live mode can arm;
• fixed-point strings for prices and quantities;
• strict, generated tool schemas with safety annotations;
• fail-closed behavior when a capability is unavailable;
• traceable alignment with exact OpenAPI operations and AsyncAPI channels; and
• repeatable MCP protocol, race, fuzz, and upstream-drift testing.

Current status

The table describes the current main branch, not the published v0.1.1 tag. The additions are unreleased and the version metadata has not yet advanced.

Area	Current behavior and limits
MCP stdio transport and generated schemas	Working
Public market data	Event contracts and perpetuals: search, market details, REST order-book snapshots, candles, and last quote. Public trade tape is event-contract only
Paper trading	In-memory balance, positions, fill journal, exact fixed-point fees, and immediate all-or-nothing fills at the current displayed touch
Live portfolio	Authenticated event-contract balance, positions, orders, and fills. Perpetual accounts and non-primary subaccounts are not supported
Live event-contract orders	Place, amend, and cancel are connected to the production API. Place/amend require process-local arming and kernel-side limits; cancel performs a resting-state check and timeout reconciliation
Live perpetual orders	Not implemented
Streaming order-book reconciliation	Not implemented; get_orderbook currently returns one public REST snapshot
kernel_status	Callable, but some readiness and arming fields still describe the old scaffold and must not be treated as authoritative
Automatic upstream specification freshness gate	Working
Production remote HTTPS/OAuth service	Not implemented
Public registry listings	Prepared, not submitted

Treat the current branch as development software, not as a published or audited trading integration. Some design and publication documents still describe the v0.1.1 scaffold; compare them with the implementation before relying on a claim. See ARCHITECTURE.md, THREAT_MODEL.md, and the release gates in PUBLICATION.md.

Agent-facing tools

Tool	Class	Current behavior
kernel_status	Read-only	Returns mode and a readiness envelope; newly added backend and arm state are not yet reflected accurately
search_markets	Read-only	Searches event-contract or perpetual markets through public REST
get_market	Read-only	Returns authoritative metadata for one event-contract or perpetual market
get_orderbook	Read-only	Returns a public REST snapshot of yes/no bid levels for either product
get_candles	Read-only	Returns 1-, 60-, or 1440-minute event-contract or perpetual OHLC buckets
get_trades	Read-only	Returns one cursor-paginated page of the public event-contract trade tape
get_last	Read-only	Returns a compact event-contract or perpetual quote and status snapshot
arm_live_trading	Destructive/control	Arms or disarms live place/amend calls for this process after an exact second acknowledgement
get_portfolio	Read-only	Returns the local paper ledger in paper mode or the authenticated event-contract portfolio in live mode
place_order	Destructive/write	Simulates an immediate fill in paper mode; submits an armed, capped event-contract order in live mode
amend_order	Destructive/write	Paper mode has no resting orders; live mode amends an armed, resting event-contract order
cancel_order	Destructive/write	Paper mode has no resting orders; live mode state-checks and cancels a resting event-contract order

Connected MCP clients also receive server-level instructions telling them to call kernel_status first, distinguish paper from live mode, and never report an action as successful unless its structured response contains ok: true. Until its readiness reporting is updated, confirm live arm state from the arm_live_trading response rather than from kernel_status.

Build and run locally

Prerequisites:

• Go 1.25.13 or newer;
• Node.js 22 only for the official MCP conformance runner; and
• a supported MCP client.

make test
make build
KALSHI_KERNEL_MODE=paper ./bin/kalshi-kernel

Paper mode is the default when KALSHI_KERNEL_MODE is unset. It intentionally discards live credential configuration.

Hermes

Add a local stdio server to ~/.hermes/config.yaml:

mcp_servers:
  kalshi-kernel:
    command: "/absolute/path/to/kalshi-kernel/bin/kalshi-kernel"
    env:
      KALSHI_KERNEL_MODE: "paper"

Restart Hermes and call kernel_status before any other tool.

Claude Code

After building the binary:

claude mcp add --scope user --transport stdio kalshi-kernel \
  --env KALSHI_KERNEL_MODE=paper -- /absolute/path/to/bin/kalshi-kernel

Then run claude mcp get kalshi-kernel or open /mcp to confirm the connection. This local setup is separate from Anthropic's public Connectors Directory, which requires a deployed remote server.

Other stdio clients

Use the standard MCP configuration shape:

{
  "mcpServers": {
    "kalshi-kernel": {
      "command": "/absolute/path/to/bin/kalshi-kernel",
      "env": {
        "KALSHI_KERNEL_MODE": "paper"
      }
    }
  }
}

Execution modes

Paper mode

KALSHI_KERNEL_MODE=paper ./bin/kalshi-kernel

Paper mode uses an in-memory simulated ledger and never submits an order to Kalshi. It starts with $100.00 by default; set KALSHI_PAPER_CASH_DOLLARS before startup to choose another balance. The ledger, positions, idempotency records, and fill journal reset when the process exits.

place_order fetches a fresh public order-book snapshot and supports only immediate, all-or-nothing marketable fills. The requested price must exactly equal the current touch and the displayed size must cover the full quantity. The simulator uses fixed-point arithmetic, applies the published fee formula, records a hash of the book used, and treats client_order_id as an idempotency key. Because paper orders never rest, amend_order and cancel_order return typed failures.

Every paper response is labeled simulated: true. Simulated fills do not predict or guarantee live fills, liquidity, latency, slippage, fees, or profitability.

Live mode

Live mode is deliberately difficult to enable:

KALSHI_KERNEL_MODE=live
KALSHI_API_KEY_ID=...
KALSHI_PRIVATE_KEY_PATH=/absolute/path/to/private-key.pem
KALSHI_LIVE_TRADING_ACK=I_UNDERSTAND_THIS_TRADES_REAL_MONEY

# Optional startup-only overrides; these are the defaults.
KALSHI_MAX_ORDER_NOTIONAL_DOLLARS=25.00
KALSHI_MAX_DAILY_NOTIONAL_DOLLARS=100.00
KALSHI_MAX_DAILY_ORDERS=200

Startup configuration selects immutable live mode and enables authenticated event-contract portfolio reads and cancellation. It does not authorize place/amend calls. Those calls require a second, process-local MCP action:

{
  "acknowledgement": "I_UNDERSTAND_THIS_TRADES_REAL_MONEY",
  "arm": true
}

Pass that object to arm_live_trading; pass the same object with arm: false to disarm. Arming is never persisted. place_order also requires a stable, caller-provided client_order_id. Place/amend requests are rejected before submission when they exceed the startup-only per-order, UTC-day notional, or UTC-day order-count limits. These counters are process-local and reset when the process restarts.

[!WARNING] cancel_order is available in configured live mode without the separate arm_live_trading step. It verifies that the order is resting before sending the cancellation. Place/amend validate price syntax and notional limits, but the current implementation does not independently compare the requested limit price with a fresh quote. Use exchange-side limits, least-privilege credentials, human review, monitoring, and an independent emergency stop.

Live account reads and writes currently support event contracts only. Perpetual-account operations and non-primary subaccounts are unavailable; omit subaccount or pass 0. Network failures after a write produce reconciled or explicitly indeterminate outcomes rather than blind retries.

Never commit credentials, private keys, or .env files. Use short-lived credentials where available, a secrets manager in production, and an account with only the privileges and capital required.

Specification-driven generation

The curated agent interface lives in specs/mcp-tools.yaml. It maps each MCP tool to exact OpenAPI operation IDs and AsyncAPI channels. Administrative and account-management endpoints are not automatically exposed merely because they exist upstream.

Four authoritative contracts are fetched from https://docs.kalshi.com:

• openapi.yaml — event-contract REST API;
• asyncapi.yaml — event-contract WebSocket API;
• perps_openapi.yaml — perpetuals REST API; and
• perps_asyncapi.yaml — perpetuals WebSocket API.

The fetcher pins HTTPS and the source hostname, limits response sizes, validates the expected dialect and non-empty surface, and records hashes and HTTP provenance. The upstream contract bodies are ignored by Git and fetched into a local cache as needed. Upstream-derived REST clients are also generated locally and excluded from source releases. Only the provenance lock, curated MCP overlay, and generated MCP tool boundary are versioned. Regeneration and testing happen in a temporary repository copy before a tested lock and MCP boundary can be promoted.

make upstream-test      # test latest contracts without requiring snapshot parity
make upstream-check     # require parity and run MCP conformance
make upstream-promote   # promote only the exact artifacts that passed

Every CI run performs the strict upstream check; CI also runs daily so drift is detected even when the repository is idle.

[!WARNING] The downloaded Kalshi contract files identify at least part of the upstream material as proprietary. They are not covered by this project's Apache-2.0 license and must not be committed or redistributed. Review THIRD_PARTY_NOTICES.md before publishing generated artifacts.

Verification

make test              # unit, integration, and contract alignment tests
make test-alignment    # OpenAPI, AsyncAPI, and MCP overlay alignment
make check-generated   # deterministic generated-code check
make test-race         # concurrent calls under Go's race detector
make test-fuzz         # execution-mode parser safety fuzzing
make conformance       # pinned official MCP protocol scenarios
make release-test      # complete local release gate
make public-check      # vulnerability, metadata, and public-readiness gate
make upstream-check    # latest Kalshi contracts plus conformance

The suite checks transport security, authentication contracts, mutation security, operation-ID uniqueness, fixed-point types, curated surface area, required-field parity, strict JSON Schemas, tool titles and safety hints, fail-closed behavior, concurrency, and Streamable HTTP negotiation.

Distribution and registries

The repository contains publication metadata for the official MCP Registry and submission dossiers for the OpenAI Plugins Directory and Anthropic directories. Metadata is preparation—not evidence of approval, endorsement, or publication.

Anthropic's current connector review criteria do not accept connectors that transfer money or other financial assets. Any Claude Connectors Directory build of this project must therefore be a distinct read-only and/or paper-only artifact with live order tools omitted, subject to Anthropic's review.

See PUBLICATION.md for the exact channel matrix, current blockers, release steps, listing copy, and review test cases. No external registry submission is performed automatically.

Contributing and security

Read CONTRIBUTING.md before opening a pull request. Report vulnerabilities privately according to SECURITY.md; do not open a public issue for a suspected credential leak or trading-safety vulnerability. General usage help belongs in SUPPORT.md.

Legal and risk notice

This software is provided for development and research. It does not provide investment, financial, legal, tax, compliance, or trading advice. Event contracts and leveraged products can result in rapid and substantial loss, including loss of the entire amount committed. You are responsible for account eligibility, jurisdictional restrictions, exchange rules, regulatory requirements, taxes, strategy, orders, and losses.

AI systems and software can misunderstand intent, produce incorrect parameters, repeat requests, or behave unexpectedly. Human review, exchange-side risk limits, least-privilege credentials, monitoring, and an independent emergency stop are required before any live deployment.

Read the full DISCLAIMER.md, PRIVACY.md, and SECURITY.md. The project is licensed under Apache License 2.0; third-party material is excluded as described in THIRD_PARTY_NOTICES.md.