Source note · Stateful tools in the Model Context Protocol

The specification states that the protocol has no concept of a state handle and that from the wire's perspective a handle is an ordinary string in a tool result and an ordinary argument to subsequent tool calls.

Checked 2026-09-05

The protocol has no concept of a state handle

Vendor: Model Context Protocol project
Product: Model Context Protocol
Subsystem: protocol
Deployment: not restricted
Region: not restricted
Release range: specification revision 2026-07-28
Checked: 2026-09-05

Sources

Model Context Protocol specification 2026-07-28, Server Features: Tools — Model Context Protocol project · tier 1 standards and regulators · Tools > Stateful Tools

Cite this note

APA

WarmTransfer. (2026, September 5). Stateful tools in the Model Context Protocol: source note statetool-no-state-handle-concept. WarmTransfer. https://warmtransfer.net/knowledge/claims/statetool-no-state-handle-concept

BibTeX

@misc{warmtransfer-claim-statetool-no-state-handle-concept,
  title  = {Stateful tools in the Model Context Protocol: source note statetool-no-state-handle-concept},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/statetool-no-state-handle-concept},
  note   = {Source note statetool-no-state-handle-concept, checked 2026-09-05}
}

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