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Version 2025-03-26
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Major changes
Other schema changes
Full changelog
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This document lists changes made to the Model Context Protocol (MCP) specification since the previous revision,
2024-11-05
.
Major changes
Added a comprehensive
authorization framework
based on OAuth 2.1 (PR
#133
)
Replaced the previous HTTP+SSE transport with a more flexible
Streamable HTTP transport
(PR
#206
)
Added support for JSON-RPC
batching
(PR
#228
)
Added comprehensive
tool annotations
for better describing tool behavior, like whether it is read-only or destructive (PR
#185
)
Other schema changes
Added
message
field to
ProgressNotification
to provide descriptive status updates
Added support for audio data, joining the existing text and image content types
Added
completions
capability to explicitly indicate support for argument autocompletion suggestions
See
the updated schema
for more details.
Full changelog
For a complete list of all changes that have been made since the last protocol revision,
see GitHub
.
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