Findings

Total findings8Across all test runs

Verified8Human-confirmed findings

Needs review0Awaiting confirmation

Upstream linked7Issues or evidence comments

8 results

VerifiedNot actionable upstream

protocol-behavior

The TypeScript SDK surfaces duplicate responses through its error callback while keeping the session usable.

Verified compatibility behavior: the TypeScript SDK reported the duplicate response through its error callback, preserved the first result, and remained usable for a same-session ping. No upstream defect was identified in the source report.

TypeScript MCP SDKv1.30.0ScenarioDuplicate ResponseEvidence1

View test run

VerifiedEvidence added to existing issue

reliability

C# MCP SDK 2.2.0 stdio cleanup waits for the five-second shutdown timeout after successful cancellation recovery.

C# MCP SDKv2.2.0ScenarioLate Response After CancellationRepositorymodelcontextprotocol/csharp-sdkEvidence1

View test run Issue #1836 Evidence comment

VerifiedEvidence added to existing issue

recovery

Python MCP SDK 2.2.0 propagates active-request session loss through the surrounding transport task context.

Python MCP SDKv2.2.0ScenarioSession Loss During Active RequestRepositorymodelcontextprotocol/python-sdkEvidence1

View test run Issue #3560 Evidence comment

VerifiedIssue opened by MCP Failure Lab

recovery

An exited stdio child leaves same-session and new Streamable HTTP sessions disconnected.

punkpeye/mcp-proxyv6.7.19ScenarioDisconnect RecoveryRepositorypunkpeye/mcp-proxyEvidence1

View test run Issue #112

VerifiedEvidence added to existing issue

recovery

An upstream HTTP disconnect can terminate the proxy and leave the active session unusable.

sparfenyuk/mcp-proxyv0.12.0ScenarioDisconnect RecoveryRepositorysparfenyuk/mcp-proxyEvidence1

View test run Issue #75 Evidence comment

VerifiedEvidence added to existing issue

compatibility

mcp-proxy 0.12.0 clean installs can resolve an incompatible MCP SDK and fail during import.

sparfenyuk/mcp-proxyv0.12.0ScenarioClean Install StartupRepositorysparfenyuk/mcp-proxyEvidence1

View test run Issue #235 Evidence comment

VerifiedIssue opened by MCP Failure Lab

reliability

A cancelled long-running operation can delay stdio client cleanup beyond the configured bound.

Official Everything Serverv2026.8.31ScenarioCleanup After TimeoutRepositorymodelcontextprotocol/serversEvidence1

View test run Issue #4846

VerifiedEvidence added to existing issue

recovery

An exited stdio child remains unavailable to later sessions while the proxy process stays running.

sparfenyuk/mcp-proxyv0.12.0ScenarioDisconnect RecoveryRepositorysparfenyuk/mcp-proxyEvidence1

View test run Issue #247 Evidence comment

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Loading findings

The TypeScript SDK surfaces duplicate responses through its error callback while keeping the session usable.

C# MCP SDK 2.2.0 stdio cleanup waits for the five-second shutdown timeout after successful cancellation recovery.

Python MCP SDK 2.2.0 propagates active-request session loss through the surrounding transport task context.

An exited stdio child leaves same-session and new Streamable HTTP sessions disconnected.

An upstream HTTP disconnect can terminate the proxy and leave the active session unusable.

mcp-proxy 0.12.0 clean installs can resolve an incompatible MCP SDK and fail during import.

A cancelled long-running operation can delay stdio client cleanup beyond the configured bound.

An exited stdio child remains unavailable to later sessions while the proxy process stays running.