[WIP] Initial A2A Integration

[jer96]

Description

This PR seeks to integrate Google's A2A protocol into Strands agents

Related Issues

• [FEATURE] Agent to Agent Communication (A2A) #24

Documentation PR

N/A

Type of Change

• New feature

Testing

• unit tests
• provided a2a_server.py and a2a_client.py files. run each script in separate terminal panes with python <file.py>.

• hatch fmt --linter
• hatch fmt --formatter
• hatch test --all
• Verify that the changes do not break functionality or introduce warnings in consuming repositories: agents-docs, agents-tools, agents-cli

Action Items & Limitations

• This is the most basic integration with A2A. A Strands agent is wrapped in an A2AAgentClass which currently only supports messages.
• Currently there is a dependency conflict with opentelemetry-exporter-otlp-proto-http and a2a-sdk dependencies. a2a-sdk relies on protobuf>=6.3.1, but opentelemetry-exporter-otlp-proto-http requires <6.0. This warranted the dependency changes to pyproject.toml and implementation changes to tracer.py. I plan on documenting the conflict and submitting issues to both the opentelemetry-exporter-otlp-proto-http and the a2a-sdk repo.
• Unit tests for the A2A integration are currently not run because of the dependency conflict mentioned above. I will investigate how to run unit tests for two separate environments in the interim.
• Native Strands tools and MCP tools are not currently supported, I will add both in a separate CR.

Checklist

• [x ] I have read the CONTRIBUTING document
• [ x] I have added tests that prove my fix is effective or my feature works
• I have updated the documentation accordingly
• I have added an appropriate example to the documentation to outline the feature
• My changes generate no new warnings
• [ x] Any dependent changes have been merged and published

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[mikegc-aws]

Thanks for this. Let's get the changes to pyproject.toml that give the feature options for otel in it's own PR so we can get this deployed ASAP and unblock A2A. Then follow up with the implementation stuff? Thoughts?

[jer96]

@mikegc-aws yes great callout, i'll extract that into a separate PR and ship that first.