Alternative · Analytics aggregator
MobyScreener vs
SimpleFunctions.
MobyScreener surfaces the live trading activity of top Polymarket participants for real-time copy-trade signals. SimpleFunctions ships the agent layer above the market itself: causal-tree thesis system, autonomous trading with a 7-gate risk cascade, calibrated world model, computed indicators across 48K+ contracts, and a 56-tool MCP server. Different surfaces, different audiences.
Verified 2026-04 · public sources only · live SF data from /calibration
Verdict
Pick the one that fits how
you actually work.
Choose SimpleFunctions if
You are building agents, autonomous trading systems, or research that needs more than trader-imitation signals — calibrated probabilities with public Brier scores, causal-tree thesis modelling with auto-evaluation cycles, regime classification across the full 48K-contract universe, computed indicators (implied yield, cliff risk, liquidity availability score), cross-venue arbitrage pairs spanning Kalshi and Polymarket, and a 56-tool MCP server that drops into Claude Code or Cursor in one line.
Choose MobyScreener if
You specifically need to monitor the live trading activity of top Polymarket participants and surface copy-trade signals in real time — that is MobyScreener's focused product. If social signal discovery from proven traders is the core of your strategy, MobyScreener is built for exactly that use case.
MobyScreener surfaces top-trader copy-trade signals on Polymarket. SimpleFunctions ships the agent layer: world model, theses, indicators, autopilot, MCP.
At a glance
Three things that
actually differ.
Everything MobyScreener gives you — live Polymarket trading signals from top participants — SimpleFunctions also gives you, on the same Polymarket feed plus Kalshi and 48K+ additional contracts.
On top of that, SF ships a causal-tree thesis system, an autonomous trading agent (Portfolio Autopilot, 1M-context LLM, 7-gate risk cascade), and 56 MCP tools that no current PM data product exposes.
SF publishes live Brier scores for itself at /api/calibration — Kalshi 0.20, Polymarket 0.12 on T-24h price, past 90 days. Most competitors claim accuracy; we let you check ours.
Side by side
9 dimensions · verified 2026-04SimpleFunctionsKalshi + Polymarket normalised, 48K+ active contracts indexed across both venues.
MobyScreenerPolymarket only, based on publicly observable product scope.
SimpleFunctionsTrade ideas at /api/public/ideas with conviction scores and catalyst labels, derived from cross-venue price signals; individual trader attribution is not a feature.
MobyScreenerLive real-time feed of top Polymarket traders' buys and sells — this is their core product, purpose-built for copy-trade insight.
SimpleFunctionsGET /api/public/market/{ticker}?depth=true returns bid/ask ladder, spread, and slippage estimate.
MobyScreenerNot publicly documented as a feature.
SimpleFunctionsImplied yield, cliff risk index, liquidity availability score, event overround, τ-days, and regime label pre-computed across 48K+ contracts at /screen.
MobyScreenerNot published; product focus is trader activity signals rather than derived contract metrics.
SimpleFunctionsLive Brier scores at /api/calibration — by venue, category, and price bucket, updated continuously.
MobyScreenerNot published.
SimpleFunctionsPOST /api/thesis/create decomposes any sentence into a causal tree, propagates probabilities, scans for tradeable edges, and runs an auto-evaluation heartbeat.
MobyScreenerNot in scope; product is a trader-activity feed, not a thesis-modelling tool.
SimpleFunctionsPortfolio Autopilot — 1M-context LLM, 13 data sources, 7-gate risk cascade including kill switch, drawdown gate, and regime check.
MobyScreenerNot in scope.
SimpleFunctions56 tools via claude mcp add simplefunctions --url https://simplefunctions.dev/api/mcp/mcp; works with Claude Code, Cursor, any MCP client.
MobyScreenerNo MCP server published.
SimpleFunctionsPublic REST + MCP + CLI reads require no auth. Thesis and intent execution: free up to 15M tokens, then pay-per-token.
MobyScreenerNot publicly documented in the candidate facts; check mobyscreener.com for current pricing.
Methodology
Verified 2026-04 from public sources only — MobyScreener's documentation, public website, and publicly observable behaviour. We never claim non-public information about MobyScreener's internals. SimpleFunctions claims on this page are computed live from /api/calibration, /api/public/cross-venue/pairs, and /api/public/markets — you can re-verify them yourself with curl.
Use cases
Same data, different
best fit per scenario.
Scenario 01
Building an AI trading agent that needs a calibrated world model of prediction market prices.
SimpleFunctions · best fit
SF exposes a world snapshot at /api/agent/world, cross-venue normalised prices, computed indicators, and 56 MCP tools designed for agent consumption. The 7-gate autopilot can execute trades autonomously once a thesis clears all risk gates.
MobyScreener
MobyScreener's product is a real-time trader feed oriented toward human copy-trading; it is not designed as an agent API substrate.
Scenario 02
Monitoring the live buying and selling activity of top Polymarket participants to mirror their trades.
SimpleFunctions
SF surfaces trade ideas at /api/public/ideas with conviction and catalyst labels, but does not track individual named trader activity or publish a copy-trade feed.
MobyScreener · best fit
This is MobyScreener's core product — they publish a real-time feed of top-trader actions specifically for this use case. If following known Polymarket participants is the strategy, MobyScreener is the right tool.
Scenario 03
Decomposing a complex geopolitical thesis into testable sub-claims and scanning for tradeable edges.
SimpleFunctions · best fit
POST /api/thesis/create decomposes the thesis into a causal tree, assigns probabilities to each node, scans Kalshi and Polymarket for matching contracts, and runs an evaluation heartbeat that refreshes confidence as news arrives.
MobyScreener
MobyScreener has no thesis modelling capability; it surfaces what traders are already doing, not a structured framework for building original research.
Scenario 04
Screening the full Kalshi and Polymarket contract universe for contracts with high implied yield or cliff risk.
SimpleFunctions · best fit
SF pre-computes IY, CRI, LAS, EE, and τ-days across 48K+ contracts at /screen, making it fast to filter for specific risk profiles without building a custom indicator pipeline.
MobyScreener
MobyScreener surfaces top-trader activity rather than computed contract-level indicators; deriving these metrics would require additional work on the user's end.
Live data
The SimpleFunctions claims on this page are not marketing copy. Brier scores, market counts, and cross-venue pair counts are computed live from /calibration, /screen, and /api/public/cross-venue/pairs. All public, all free, all CC-BY-4.0.
FAQ
What does MobyScreener do that SimpleFunctions doesn't?+
MobyScreener specializes in surfacing the real-time trading activity of top Polymarket participants, allowing users to follow and copy proven traders. SimpleFunctions does not track individual trader identities or publish a live copy-trade feed. If your strategy depends on social-signal discovery from named participants on Polymarket, MobyScreener serves that use case directly and is the more focused tool for it.
How does the SimpleFunctions thesis system work?+
POST /api/thesis/create accepts any natural-language sentence — for example, 'a rate cut will happen before Q3' — and decomposes it into a causal tree of testable sub-claims. Each node receives a probability estimate. SF then scans Kalshi and Polymarket for contracts matching each sub-claim and computes implied edges. A background evaluation heartbeat reruns news scanning, price refresh, milestone checks, and LLM evaluation on a rolling basis, updating confidence scores as conditions change. Public theses are forkable via the API.
Does SimpleFunctions track top trader activity?+
SF publishes trade ideas at /api/public/ideas with conviction scores and catalyst labels, derived from cross-venue price signals and computed indicators — not from individual trader attribution. SF also surfaces cross-venue arbitrage pairs at /api/public/cross-venue/pairs. If you specifically need to see what named top Polymarket participants are buying and selling in real time, MobyScreener is the purpose-built product for that.
What can I do with SimpleFunctions' 56-tool MCP server?+
The MCP server is available in one command: claude mcp add simplefunctions --url https://simplefunctions.dev/api/mcp/mcp. It exposes market search, thesis creation and signal injection, portfolio autopilot controls, calibration data, cross-venue pair scanning, orderbook depth queries, and more — all usable directly from Claude Code, Cursor, or any MCP-compatible client without writing custom API integration code.
How does SimpleFunctions measure its own accuracy?+
SF publishes live Brier scores at /api/calibration, segmented by venue, category, and price bucket, computed over the past 90 days. Current baselines: Kalshi 0.20, Polymarket 0.12 on T-24h prices. These figures are recomputable from the raw endpoint — no trust required. MobyScreener's product focus is on trader activity signals rather than calibrated probability forecasting, so accuracy metrics of this kind are not central to what they offer.
Does MobyScreener cover Kalshi contracts?+
Based on publicly available information, MobyScreener's product is focused on Polymarket trader activity. SimpleFunctions covers both Kalshi and Polymarket with 48K+ normalised contracts across both venues, plus cross-venue matched pairs at /api/public/cross-venue/pairs for arbitrage scanning across the full combined universe.
Can SimpleFunctions execute trades autonomously?+
Yes. Portfolio Autopilot uses a 1M-context LLM, 13 data sources, and a 7-gate risk cascade — including kill switch, position limits, drawdown gate, and regime classification — before placing any order. Trades are only executed after all gates clear. MobyScreener is a signal discovery product and does not offer autonomous execution.
Which platform is better for a researcher building a quantitative model?+
It depends on the research question. If the goal is modelling contract-level signals — implied yield, cliff risk, liquidity, calibrated probability — SF provides pre-computed indicators across 48K+ contracts, a public Brier score baseline, and a causal thesis framework. If the goal is analysing the behaviour of top Polymarket traders or building copy-trade strategies around named participants, MobyScreener's feed is the more direct data source.
Start for free.
Public endpoints are free for normal usage and rate-limited for reliability. Authenticated endpoints are free up to 15M tokens, then pay per token. No credit card to start.