Microsoft has released Semantic Kernel Python 1.45.0, with changes to how plugins handle requests and downloaded files. The release also removes a service authentication mode for Copilot Studio agents, a breaking change for developers relying on it.
Microsoft AI Watch analysis
What happened
The Python 1.45.0 release notes list the change to Copilot Studio authentication alongside several updates affecting plugin and agent integrations. OpenAPI plugin requests now pin the validated address; session download filenames are encoded and validated; and MCP server tool names are made consistent.
The notes also list validation for CrewAI task identifiers and shared HTTP request validation utilities across Python and .NET. These are concrete changes to the framework’s integration plumbing, rather than a new model or a change to what Semantic Kernel is for.
Why it matters
Semantic Kernel connects AI applications to tools and external services, so the details of how those connections handle addresses, filenames and task identifiers matter to developers building on it. The release gives them specific integration changes to assess, while the Copilot Studio authentication removal means some existing setups may need attention before upgrading.
Our read
This is an unflashy release with useful work in the places where agent frameworks meet the rest of a software stack. Check whether your Copilot Studio setup uses the removed authentication mode, then test the upgrade against your plugins and integrations. “Minor version” is not a magic spell that makes breaking changes disappear.
What to watch
- Whether the authentication change affects your Copilot Studio agent configuration.
- How the updated request and filename validation behaves in existing integrations.
- Whether the release notes or later documentation clarify migration steps for affected users.
Discussion spark: When upgrading an AI framework, should teams prioritise the new validation and integration changes, or wait until they have confirmed that breaking changes will not disrupt existing agents?
Sources and evidence
- python-1.45.0 (6 October 2026, 12:55 UTC)
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