MCP HeartbeatTHE MCP OBSERVATORY
Public workspace

Explore

Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Other

Crosswire — Polymarket & Kalshi Arbitrage

By crosswire-api.com Verified namespace

Cross-venue Polymarket+Kalshi arbitrage: resolution mismatch, void risk & settlement divergence.

WebsiteSource code
Connect to Crosswire — Polymarket & Kalshi Arbitrage
Checks passed
15 / 22

0 failed · 7 not measured

Median response
413 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
2

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 374 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name Crosswire.

  • Pass
    Lists tools

    tools/list returned 2 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 413 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 448 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    6 of 6 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-06-21T16:50:22.811968Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using Crosswire — Polymarket & Kalshi Arbitrage

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http crosswire-polymarket-kalshi-arbitrage https://api.crosswire-api.com/mcp

Capabilities

Tools 2

check_resolution_risk

Pre-trade safety check for cross-venue event markets (crypto oracle-divergence pairs, metered; World Cup football, free). Flags resolution mismatches, void-rule divergence, scope differences (e.g. 90-minute vs extra-time; matched vs differing strike), settlement-source and -timing gaps, stale data, and thin liquidity between the two Polymarket and Kalshi legs BEFORE you execute both. Returns a machine-readable verdict — execution_verdict: safe / caution / block — inside a full Fungibility & Settlement Audit Object (FSAO) with structured findings, top-level divergence flags, venue rule overrides, fee-adjusted spread, and verdict reasons. Identify the pair by EITHER canonical_event_id (a live pair id from list_covered_events — the metered 'crypto:' inventory rolls daily, so fetch a current id there rather than reusing an old one; the free 'wc26:' World Cup pairs are stable) OR market_a + market_b (one Polymarket conditionId + one Kalshi ticker, order-insensitive). If the pair is not covered, returns a non-error coverage reply (covered: false) naming the covered inventories (free World Cup football + metered crypto pairs) and the coverage cutoff instead of an FSAO.

Discovered
list_covered_events

Free discovery of everything check_resolution_risk can audit across both inventories — the free World Cup football pairs and the metered crypto oracle-divergence pairs (the 'crypto:' namespace is the paid surface: $0.02 USDC per call after 3 free calls/day). Returns the covered canonical events, their per-outcome pair ids (…#home / #draw / #away for football), the Polymarket conditionIds and Kalshi tickers with outcome labels for each pair, match dates, the frozen ruleset_sha pinning the identity graph, the coverage kickoff cutoff, and snapshot freshness. Use a returned pair_id (or a pair's two market ids) as input to check_resolution_risk.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected374 ms2
Connected452 ms2

Related servers

All alternatives

Same function and industry, ranked by checks passed then median latency.

  • Responded16 / 22 checks passed
    Catalyst evidence graph

    catalystproject.aiVerified

    Findings on what compounds and supplements do in the body, with evidence strength, quote and paper.

    OtherOther

    • Passed: Handshake
    • Passed: Tools listed
    • Passed: Updated recently

    Median latency 699 ms · Last checked

  • Responded15 / 22 checks passed
    wcway

    wcway.comVerified

    Find the nearest public toilet worldwide. Read-only tools, no account, no API key.

    OtherOther

    • Passed: Handshake
    • Passed: Tools listed
    • Passed: Updated recently

    Median latency 49 ms · Last checked

  • Responded15 / 22 checks passed
    Pick My Costume

    pickmycostume.comVerified

    Recommends Halloween costumes you can actually build, with step-by-step DIY build guides.

    OtherOther

    • Passed: Handshake
    • Passed: Tools listed
    • Passed: Updated recently

    Median latency 57 ms · Last checked

  • Responded15 / 22 checks passed
    Routine Run: write a routine

    routinerun.comVerified

    Write a step-by-step routine and get a link that opens it in Routine Run on iPhone. No sign-in.

    OtherOther

    • Passed: Handshake
    • Passed: Tools listed
    • Passed: Updated recently

    Median latency 62 ms · Last checked

Explore alternatives to Crosswire — Polymarket & Kalshi Arbitrage