In the stdio transport the client launches the MCP server as a subprocess, and messages are newline-delimited on stdin and stdout and MUST NOT contain embedded newlines.

Checked 2026-09-30

Vendor
Model Context Protocol project
Product
MCP specification
Subsystem
stdio transport
Deployment
local-subprocess
Region
not restricted
Release range
MCP revisions 2024-11-05 through 2026-07-28
Checked
2026-09-30

Sources

Cite this note

APA

WarmTransfer. (2026, September 30). Model Context Protocol transports compared: source note mcp-transport-differences-stdio-framing. WarmTransfer. https://warmtransfer.net/knowledge/claims/mcp-transport-differences-stdio-framing

BibTeX

@misc{warmtransfer-claim-mcp-transport-differences-stdio-framing,
  title  = {Model Context Protocol transports compared: source note mcp-transport-differences-stdio-framing},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/mcp-transport-differences-stdio-framing},
  note   = {Source note mcp-transport-differences-stdio-framing, checked 2026-09-30}
}

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