pypi / wayflowcore
wayflowcore
What changed in wayflowcore 26, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-19.
7 breaking2 deprecations8 new APIs and options2 behavior and defaults5 fixes and other
See which of these apply to your code, ranked, in your agent:
npx @unstale/cli initwayflowcore 2624 changes
Breaking changes 7
Deprecated Agent.execute() was removed; use conversation.execute() instead.
Pass a Step to begin_step instead of using begin_step_name.
Replace begin_step_name with begin_step, passing a Step.
Replace ChatHistoryContextProvider with FlowContextProvider using GetChatHistoryStep.
Use conversation.execute() in place of the removed deprecated Agent.execute() and Flow.execute() methods.
Deprecated Flow.execute() was removed; use conversation.execute() instead.
Templates can no longer access object attributes; only safe dictionary and loop properties are allowed, so previously working templates may raise security errors.
Deprecations 2
Use FlowContextProvider with GetChatHistoryStep in place of ChatHistoryContextProvider.
Tool names are now subject to valid-name enforcement; whitespace or special characters raise a deprecation warning, and will cause an error in the next cycle.
New APIs and options 8
Adds support for streaming MCP tool output, particularly useful when tool execution is long but streamable.
WayFlow supports agent-to-agent workflows.
A built-in server lets developers deploy, run, and integrate agents in production environments.
A new mode better guides delegation and enforces handoff behavior when required.
Developers can now build hierarchical ManagerWorkers.
WayFlow supports connecting to OpenAI’s latest response APIs.
Swarm and ManagerWorkers can now be integrated directly into Flows.
Plugins let developers extend or create Tools and Steps and integrate custom components with serialization and deserialization.
Behavior and default changes 2
Use GetChatHistoryStep with FlowContextProvider in place of ChatHistoryContextProvider.
Swarm and ManagerWorkers now support multiple tool calls per turn.
Fixes and other changes 5
Fixes compatibility issues with Gemini models.
Fixes bugs related to MCP session handling.
Fixes bugs related to swarm execution.
Internal sanitization of agent and flow names prevents LLM API errors for multi-agent workflows.
Default input values for agents are now respected.