FastMCP 3.0 supports component versioning — serve @tool(version="2.0") alongside older versions from one codebase. This could help us evolve tool signatures without breaking existing agent workflows.
What's available:
@tool(version="2.0") decorator parameterVersionFilter transform for automatic highest-version selection- Clients can request specific versions
Value: Would let us iterate on tool signatures (e.g. adding structured return types, changing parameters) without breaking agents pinned to older behavior.
Ref: https://github.com/PrefectHQ/fastmcp/releases/tag/v3.0.0
FastMCP 3.0 supports component versioning — serve
@tool(version="2.0")alongside older versions from one codebase. This could help us evolve tool signatures without breaking existing agent workflows.What's available:
@tool(version="2.0")decorator parameterVersionFiltertransform for automatic highest-version selectionValue: Would let us iterate on tool signatures (e.g. adding structured return types, changing parameters) without breaking agents pinned to older behavior.
Ref: https://github.com/PrefectHQ/fastmcp/releases/tag/v3.0.0