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Install in OpenClaw
/install dolph-market-maker
Description
Places GTC limit orders on both sides (bid/ask) of liquid Polymarket markets. Finds active markets with >$10k 24h volume, mid-range prices, and ample time to...
README (SKILL.md)
Polymarket Market Maker
A market-making strategy that places GTC (Good-Till-Cancelled) limit orders on both sides of liquid Polymarket prediction markets, capturing the bid/ask spread.
Strategy
-
Market Selection: Finds active markets with:
- 24h volume > $10,000 (liquid enough to fill)
- Price (YES probability) between 0.15 and 0.85 (avoids near-certain outcomes)
- Resolves > 4 hours away (enough time to get fills)
- No taker fees (
is_paid=False) — 10% fee kills the edge
-
Pricing: Fetches the live CLOB midpoint for each market and quotes:
- YES buy limit at
mid - 0.02(2¢ below mid) - NO buy limit at
(1 - mid) - 0.02(2¢ below NO mid)
- YES buy limit at
-
Order Management: Cancels existing open orders before placing new ones each run.
-
Limits: Max $5 per order, max 3 markets per run.
Requirements
Environment variables (required):
| Variable | Required | Description |
|---|---|---|
SIMMER_API_KEY |
✅ Yes | Your Simmer API key — get it at simmer.markets/dashboard → SDK tab |
TRADING_VENUE |
Optional | polymarket (default) or sim for paper trading with virtual $SIM |
Python dependency: simmer-sdk — install with pip install simmer-sdk
Setup
export SIMMER_API_KEY=sk_live_... # required
export TRADING_VENUE=sim # optional: paper mode with $SIM
pip install simmer-sdk
Usage
# Dry run (default)
python market_maker.py
# Live trading
python market_maker.py --live
# Show current positions
python market_maker.py --positions
# Show config
python market_maker.py --config
# Set config
python market_maker.py --set max_order_usd=10.0
Config (env vars)
| Env Var | Default | Description |
|---|---|---|
SIMMER_MM_MAX_ORDER_USD |
5.0 | Max USD per limit order |
SIMMER_MM_MAX_MARKETS |
3 | Max markets per run |
SIMMER_MM_MIN_VOL_24H |
10000 | Min 24h volume filter |
SIMMER_MM_SPREAD_OFFSET |
0.02 | How far below mid to quote (2¢) |
SIMMER_MM_MIN_PRICE |
0.15 | Min YES price to consider |
SIMMER_MM_MAX_PRICE |
0.85 | Max YES price to consider |
SIMMER_MM_MIN_HOURS_TO_RESOLVE |
4 | Min hours to resolution |
Usage Guidance
This skill appears to implement what it claims (a Polymarket market maker) and only needs a Simmer API key and the simmer-sdk package — both reasonable for trading. However: 1) the package lacks an external homepage and the registry metadata is inconsistent about required environment variables, so verify the source and trust the owner before installing; 2) inspect the simmer-sdk package (where network/trade calls are implemented) to confirm it doesn't do unexpected work or store your API key insecurely; 3) check what permissions the SIMMER_API_KEY grants (ensure it isn't broader than necessary, e.g., doesn't grant withdrawals); 4) run in paper/sim mode first (TRADING_VENUE=sim and --dry run) and review logs; 5) consider running in an isolated environment and rotate the API key after initial tests. If you want, I can list the specific lines that access external endpoints and the exact manifest mismatches to help you audit further.
Capability Analysis
Type: OpenClaw Skill
Name: dolph-market-maker
Version: 1.0.0
The skill bundle implements a legitimate market-making strategy for Polymarket using the simmer-sdk. The code in market_maker.py performs market filtering, fetches order book midpoints from clob.polymarket.com, and manages limit orders as described in SKILL.md. There are no signs of data exfiltration, malicious execution, or prompt injection; the use of the SIMMER_API_KEY and network requests are consistent with the tool's stated purpose of automated trading.
Capability Assessment
Purpose & Capability
The SKILL.md and market_maker.py implement a Polymarket market‑maker using a Simmer SDK and a Polymarket CLOB endpoint; the required simmer SDK and SIMMER_API_KEY are coherent with that purpose. However, the top-level registry metadata in the evaluation header claimed no required env vars while clawhub.json and SKILL.md both require SIMMER_API_KEY — a manifest inconsistency that reduces trust in the package metadata.
Instruction Scope
Runtime instructions and code stay within the stated domain: fetching markets, computing midpoints (via CLOB endpoint), cancelling and placing GTC orders, and managing a small config. There are no instructions to read unrelated host files, crawl shell history, or exfiltrate arbitrary data to unknown endpoints. The only network targets are the Simmer API (via simmer-sdk/_request) and Polymarket CLOB at clob.polymarket.com.
Install Mechanism
No install script is included (instruction-only install), and required dependency is a pip package (simmer-sdk) — which is an expected delivery method. There are no arbitrary downloads or extract actions in the skill files. Still, the package lacks a homepage and the owner/publish provenance is weak; you should verify the simmer-sdk package source and integrity before installing.
Credentials
The skill requires a single API key (SIMMER_API_KEY) and an optional TRADING_VENUE — both reasonable for a trading bot. The concern is the manifest mismatch: some registry metadata claimed no required env vars while the bundled clawhub.json and SKILL.md require SIMMER_API_KEY. That mismatch could cause users to miss that they're exposing an API key to this code. Also confirm what rights the SIMMER API key grants (trading vs read-only) before using it for live trades.
Persistence & Privilege
The skill is not flagged always:true and is user-invocable only; it does not request system‑wide privileges. It uses load_config/update_config to manage its own config files (normal). Autonomous invocation is allowed by default but not combined here with other high‑risk flags.
How to Use
- Make sure OpenClaw is installed (local or Docker)
- Run the install command in chat:
/install dolph-market-maker - After installation, invoke the skill by name or use
/dolph-market-maker - Provide required inputs per the skill's parameter spec and get structured output
Version History
v1.0.0
- Renamed skill to "Simmer Market Maker" with updated display name and metadata.
- Enhanced market selection criteria: now targets Polymarket markets with >$10k 24h volume, mid-range prices, sufficient time to resolve, and no taker fees.
- GTC limit orders are now quoted at 2¢ below the CLOB midpoint on both YES and NO sides, aiming to capture bid/ask spread.
- Order management improved: cancels previous orders before placing new ones.
- Added configurable environment variables for order size, market count, volume threshold, spread offset, and price/time filters.
- Updated usage instructions and requirements for easier setup and paper trading mode.
Metadata
Frequently Asked Questions
What is Simmer Market Maker?
Places GTC limit orders on both sides (bid/ask) of liquid Polymarket markets. Finds active markets with >$10k 24h volume, mid-range prices, and ample time to... It is an AI Agent Skill for Claude Code / OpenClaw, with 84 downloads so far.
How do I install Simmer Market Maker?
Run "/install dolph-market-maker" in the OpenClaw or Claude Code chat to install it in one step — no extra setup required.
Is Simmer Market Maker free?
Yes, Simmer Market Maker is completely free, licensed under MIT-0. You can download, install and use it at no cost.
Which platforms does Simmer Market Maker support?
Simmer Market Maker is cross-platform and runs anywhere OpenClaw / Claude Code is available (cross-platform).
Who created Simmer Market Maker?
It is built and maintained by richducat (@richducat); the current version is v1.0.0.
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