Summary
sandbox.mcp.payloadSizeThreshold (and related payload fields) are documented but appear to be ignored at compile time, so generated workflows still export the default MCP_GATEWAY_PAYLOAD_SIZE_THRESHOLD=524288.
Repro
Use frontmatter like:
sandbox:
mcp:
container: ghcr.io/github/gh-aw-mcpg
payloadSizeThreshold: 65536Compile workflow and inspect generated lock/setup step.
Expected: MCP_GATEWAY_PAYLOAD_SIZE_THRESHOLD=65536
Actual: MCP_GATEWAY_PAYLOAD_SIZE_THRESHOLD=524288
Likely cause
extractMCPGatewayConfig() does not extract payload fields from frontmatter (payloadSizeThreshold, payload-size-threshold, payloadDir, payloadPathPrefix), so values never reach workflowData.SandboxConfig.MCP before mcp_setup_generator applies defaults.
Notes
This also makes the documented frontmatter setting effectively non-functional in current builds.
Summary
sandbox.mcp.payloadSizeThreshold(and related payload fields) are documented but appear to be ignored at compile time, so generated workflows still export the defaultMCP_GATEWAY_PAYLOAD_SIZE_THRESHOLD=524288.Repro
Use frontmatter like:
Compile workflow and inspect generated lock/setup step.
Expected:
MCP_GATEWAY_PAYLOAD_SIZE_THRESHOLD=65536Actual:
MCP_GATEWAY_PAYLOAD_SIZE_THRESHOLD=524288Likely cause
extractMCPGatewayConfig()does not extract payload fields from frontmatter (payloadSizeThreshold,payload-size-threshold,payloadDir,payloadPathPrefix), so values never reachworkflowData.SandboxConfig.MCPbeforemcp_setup_generatorapplies defaults.Notes
This also makes the documented frontmatter setting effectively non-functional in current builds.