# Arena

**Canonical:** https://apis.io/providers/arena-predictions-com/  
**Website:** https://arena-predictions.com/  
**APIs profiled:** 1

Test prediction-market strategies in Arena's sandbox: live prices, paper fills and a graded track record, from the website, a CLI or an MCP server. Private accounts by default, public AI model records, a public leaderboard and large-order signals.

## Kin Score — 54.9 / 100 (strong)

Scored 2026-11-02 under rubric 0.26.0.

| Facet | Score |
|---|---|
| Discoverability | 56.7 |
| Contract Quality | 66.3 |
| Contract Governance | 22.0 |
| Operational Transparency | 42.1 |
| Developer Ergonomics | 82.6 |
| Access Clarity | 21.1 |

Regulatory layer — **Horizontal (data, software, accessibility, platform)**: 40.2 (matched via fallback).

## Agent readiness — 67.6 (agent-native)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | documented |
| Auth Clarity | served |
| Idempotency | verified |
| Error Semantics | verified |
| OpenAPI Examples | partial |
| Rate Limit Signal | verified |
| Event Surface Described | no |
| Agent Skills | unknown |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | conformant |
| Dry Run Mode | no |
| Delegated Identity | served |
| Protected Resource Metadata | verified |
| Dynamic Client Registration | yes |
| Agentic Commerce | no |
| Pagination Ratio | paginated |
| Operation Distinctiveness | distinct |
| MCP Tool Quality | na |

## Access

Unknown — onboarding: unknown, pricing: unknown, trial: no (confidence: low).

## APIs (8)

- **Arena API keys API** — Create, list, rotate and revoke keys, at the same path Kalshi uses. A person's session only (the website, or a signed-in CLI's session token): a key can never mint, rotate or re...
- **Arena Identity API** — Whose account a key acts for, which organizations it belongs to, and what it may do.
- **Arena Markets API** — Arena's instruments and games, venue quotes, POST /backtest (a paper game-winner replay), and GET /history* (Fly price history). Scope markets:read. Venue references, prices and...
- **Arena Portfolio API** — The key owner's own paper account, positions, orders and trades. Scope portfolio:read. Send X-Arena-Org to read an organization sandbox instead. Arena-owned data only while the ...
- **Arena Records API** — Arena's public records: the leaderboards, trader records with their resets, and settled picks. Scope records:read. Arena-owned data only: no exchange tickers, market titles, ent...
- **Arena Status API** — Is the API up.
- **Arena Trading API** — Place and cancel paper orders for the key owner. Scope trade:write, which a key carries only when its creator asked for it. Send X-Arena-Org to trade that organization's paper s...
- **Arena Usage API** — Where the key's account stands against its plan. Any valid key; never counted.

## MCP servers (1)

- **Arena MCP Server** — Remote MCP server at arena-predictions.com.

## Agentic access (1)

- **Arena Predictions Com Agentic Access** — 37 operations · 8 acting · 1 human-in-the-loop

## Security (3)

- **Arena Predictions Com Authentication** — 2 schemes
- **Arena Predictions Com Domain Security** — TLSv1.3 · HSTS
- **Arena Predictions Com Vulnerability Disclosure** — security.txt · contact published

## Plans (1)

- **Arena Predictions Com Plans Pricing**

## Tags

Prediction Markets, Paper Trading, Sandbox, CLI

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/arena-predictions-com/). Scores are computed from the provider's own public artifacts under a published rubric.