SimpleFunctions

Alternative · AI agent

Octagon AI vs
SimpleFunctions.

SimpleFunctions and Octagon AI both produce event probability estimates, but from opposite starting points. Octagon AI is a finished forecasting service — it runs the research, runs the model, and hands you a forecast. SimpleFunctions ships the building blocks for teams that want to construct their own agent layer: a causal-tree thesis system with auto-evaluation cycles, a Portfolio Autopilot backed by a 1M-context LLM and 7-gate risk cascade, computed indicators across 48K+ active contracts, and a 56-tool MCP server that drops into any MCP client in one command.

Verified 2026-04 · public sources only · live SimpleFunctions data from /calibration

Category

AI agent

Differences

9

Use cases

4

Verified

2026-04

Verdict

Pick the one that fits how
you actually work.

Choose SimpleFunctions if

You are building agents, autonomous trading systems, or research pipelines that need programmable primitives — not a black-box forecast. SimpleFunctions gives you a causal-tree thesis system that decomposes any sentence into testable sub-claims, propagates probabilities, and runs an evaluation heartbeat; a Portfolio Autopilot with 1M-context LLM and 7-gate risk cascade; computed indicators (implied yield, cliff risk, liquidity availability score) across 48K+ contracts; public Brier calibration scores; and a 56-tool MCP server.

Choose Octagon AI if

Octagon AI is the right choice when your team needs a finished forecasting output without building any API integration or inference pipeline. If the goal is to receive AI-generated event probability estimates from a managed deep-research system — not to author theses, inject signals, or orchestrate an agent — Octagon's service model is purpose-built for that workflow.

Different product surfaces: Octagon AI delivers finished AI-generated forecasts; SimpleFunctions ships the agent layer — thesis system, autopilot, MCP, indicators — for teams who build.

At a glance

Three things that
actually differ.

01

Everything Octagon AI gives you — AI-generated event probability estimates and deep-research forecasts over prediction-market events — SimpleFunctions also gives you, computed live from Kalshi and Polymarket across 48K+ active contracts.

02

On top of that, SF ships a causal-tree thesis system with signal injection and auto-evaluation heartbeats, a Portfolio Autopilot with 7-gate risk cascade, and 56 MCP tools that no current AI forecasting product exposes.

03

SF publishes its own Brier scores live at /api/calibration — Kalshi 0.20, Polymarket 0.12 on T-24h price, past 90 days — so you can audit SF's accuracy the same way you audit any model's outputs.

Side by side

9 dimensions · verified 2026-04
Cross-venue prices

SimpleFunctionsKalshi and Polymarket normalised prices across 48K+ active contracts, queryable via REST or MCP.

Octagon AIEvent probability estimates derived from Octagon's internal research model; not a raw price aggregation layer.

Orderbook depth

SimpleFunctionsGET /api/public/market/{ticker}?depth=true returns the bid/ask ladder, spread, and slippage estimate.

Octagon AINot in scope; Octagon surfaces forecast conclusions, not live orderbook data.

Computed indicators

SimpleFunctionsImplied yield, cliff risk index, liquidity availability score, event overround, and regime label pre-computed across 48K contracts at /screen.

Octagon AINot published; Octagon surfaces forecast outputs, not tradeable signal metrics derived from market microstructure.

Calibration data

SimpleFunctionsLive Brier scores at /api/calibration — by venue, category, and price bucket — updated continuously.

Octagon AIModel accuracy metrics not publicly published.

Causal thesis system

SimpleFunctionsPOST /api/thesis/create decomposes any natural-language sentence into a causal sub-claim tree, propagates probabilities, scans Kalshi and Polymarket for tradeable edges, and runs an evaluation heartbeat.

Octagon AINot in scope; Octagon performs its own internal research pipeline and does not expose user-defined thesis decomposition or signal injection.

Autonomous trading

SimpleFunctionsPortfolio Autopilot uses a 1M-context LLM, 13 data sources, and a 7-gate risk cascade (kill switch, drawdown gate, regime check) before any execution.

Octagon AINot in scope; Octagon is a forecasting platform, not an execution or portfolio management layer.

MCP server

SimpleFunctions56 tools via claude mcp add simplefunctions --url https://simplefunctions.dev/api/mcp/mcp — works with Claude Code, Cursor, and any MCP client.

Octagon AINo MCP server published.

API access model

SimpleFunctionsOpen REST API for reads; users author their own theses, inject signals, and control execution logic programmatically.

Octagon AIOctagon manages the research and model architecture internally; customers receive forecast outputs, not authorship or programmable control over the pipeline.

Pricing

SimpleFunctionsPublic REST, MCP, and CLI reads require no authentication. Thesis and intent execution is free up to 15M tokens, then pay-per-token.

Octagon AIPricing not publicly listed; sold as a managed forecasting service.

Methodology

Verified 2026-04 from public sources only — Octagon AI's documentation, public website, and publicly observable behaviour. We never claim non-public information about Octagon AI'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

A developer wants to build an AI agent that monitors prediction markets, executes trades, and evaluates geopolitical theses autonomously.

SimpleFunctions · best fit

SF is the native fit. The 56-tool MCP server connects the agent to live market data in one command; the thesis system decomposes research into a causal sub-claim tree with auto-evaluation; Portfolio Autopilot handles execution through a 7-gate risk cascade without manual intervention.

Octagon AI

Octagon produces finished forecast outputs, not an agent-composable API layer. A developer would need to reverse-integrate Octagon's forecasts into a custom pipeline rather than build natively on programmable primitives.

Scenario 02

A research team needs AI-generated probability estimates on a set of geopolitical and macro events but has no engineering bandwidth to build or maintain a data pipeline.

SimpleFunctions

SF can deliver the probabilities via REST or MCP, but the team would still need to author theses and configure the evaluation pipeline — a lightweight but real integration requirement.

Octagon AI · best fit

Octagon is the better fit here. Its deep-research model is designed to perform the research and surface the forecast as a finished product, with no API integration work required from the customer.

Scenario 03

An analyst wants to decompose a complex multi-leg thesis (e.g., 'Fed cuts in Q3 → volatility rises → prediction market mispricing appears') into individually testable claims and track each leg against live market prices.

SimpleFunctions · best fit

SF's thesis system is built exactly for this: POST /api/thesis/create accepts a natural-language sentence, decomposes it into a causal tree of sub-claims, maps each to live Kalshi and Polymarket contracts, and runs an ongoing evaluation heartbeat that updates confidence as news and prices move.

Octagon AI

Octagon generates a single model-driven forecast; it does not expose user-defined causal decomposition, sub-claim tracking, or signal injection at the API layer.

Scenario 04

A quant researcher wants to verify a forecasting system's historical accuracy before committing capital to its signals.

SimpleFunctions · best fit

SF publishes its own Brier scores at /api/calibration — broken down by venue, category, and price bucket — so accuracy claims are machine-verifiable with a single curl call.

Octagon AI

Octagon's model accuracy metrics are not publicly published, so external calibration verification would depend on the customer conducting their own holdout evaluation.

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 is SimpleFunctions' causal thesis system and how does it differ from Octagon AI's approach?+

SF's thesis system accepts any natural-language sentence via POST /api/thesis/create, decomposes it into a directed acyclic graph of testable sub-claims, propagates probabilities through the tree, scans Kalshi and Polymarket for contracts that map to each node, and runs a continuous evaluation heartbeat — news scan, price refresh, milestone check, LLM evaluation, confidence update. You inject signals via /api/thesis/{id}/signal and fork public theses. Octagon AI performs its own internal research and surfaces a finished forecast; users do not author or control the decomposition logic.

Does SimpleFunctions have an MCP server?+

Yes. SF exposes 56 tools via the Model Context Protocol. Add it to any MCP client with: claude mcp add simplefunctions --url https://simplefunctions.dev/api/mcp/mcp. It works with Claude Code, Cursor, and any other MCP-compatible host. The tools cover market search, thesis authorship, orderbook depth, cross-venue arbitrage pairs, computed indicators, world snapshot, and more. Octagon AI does not publish an MCP server.

What is Portfolio Autopilot?+

Portfolio Autopilot is SF's autonomous trading agent. Before executing any position, it passes a 7-gate risk cascade: kill switch check, position limits, drawdown gate, regime classification, liquidity availability score, conviction threshold, and correlation guard. It runs on a 1M-context LLM with 13 live data sources feeding the decision loop. It is distinct from the thesis system — Autopilot manages execution, while the thesis system manages belief propagation. Octagon AI does not offer an execution or portfolio management layer.

How does SF's calibration endpoint work, and why does it matter?+

GET /api/calibration returns SF's own Brier scores, computed against resolved contracts over the past 90 days, broken down by venue (Kalshi, Polymarket), category, and price bucket. Current figures: Kalshi 0.20, Polymarket 0.12 on T-24h price. This is SF auditing its own accuracy publicly — you can re-run the query with curl at any time to get a fresh result. Most forecasting products, including Octagon AI, do not publish equivalent machine-readable calibration data.

Can I access raw orderbook depth through SimpleFunctions?+

Yes. GET /api/public/market/{ticker}?depth=true returns the full bid/ask ladder, spread, and slippage estimate for any contract on Kalshi or Polymarket. This is in addition to normalised prices, computed indicators, and historical data. Cross-venue arbitrage opportunities are available at /api/public/cross-venue/pairs?preset=arb. Octagon AI does not expose live orderbook data — its product layer is forecast outputs, not market microstructure.

Is SimpleFunctions a good Octagon AI alternative for AI agent developers?+

If you are building an agent that needs to reason about prediction markets — not just receive a finished forecast — SF is the more appropriate substrate. The 56-tool MCP server integrates with Claude Code or Cursor in one command. The thesis system gives the agent a structured causal model to work from. The Autopilot handles execution. Octagon AI is optimised for teams that want to consume AI-generated forecasts as a finished output, not teams that want to build the inference and execution layer themselves.

What computed indicators does SimpleFunctions provide?+

SF pre-computes six indicators across all 48K+ active contracts: IY (implied yield — annualised return to settlement), CRI (cliff risk index — probability mass concentrated near expiry), LAS (liquidity availability score — depth-adjusted fill quality), EE (event overround — total probability excess above 1.0), τ-days (time to settlement), and regime label (adverse-selection classification). These are queryable at /screen and via MCP. Octagon AI surfaces forecast probabilities; it does not publish tradeable signal metrics derived from market microstructure.

Does Octagon AI have a public REST API?+

Based on publicly available information, Octagon AI operates as a managed deep-research forecasting service. No public REST API documentation has been published as of 2026-04. If you need a programmable API for prediction market data, thesis authorship, and agent orchestration, SF's REST API, CLI, and MCP server are openly documented and require no authentication for read access.

Same category

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