Python: Add Python parity for InvokeMcpTool in declarative workflow

[Peter Ibekwe (peibekwe)]

Motivation and Context

Adds Python implementation of the InvokeMcpTool declarative workflow action, achieving parity with the .NET implementation. Workflow authors can now dispatch MCP calls directly from YAML.

The PR also includes sample to showcase the use of the new action.

Fixes #5625

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[Evan Mattson (moonbox3)]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/declarative/agent_framework_declarative/_workflows
_declarative_builder.py	375	11	97%	177, 209, 273, 364, 386, 447, 449, 477, 541, 544, 965
_executors_mcp.py	264	29	89%	136, 139, 331–334, 337–338, 381, 384, 390, 393, 402, 412, 416, 431, 434, 447, 450, 461–463, 475–477, 514–515, 577, 608
_factory.py	151	2	98%	469, 524
_mcp_handler.py	184	7	96%	92, 271–272, 390–392, 413
TOTAL	32711	3747	88%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
6369	30 💤	0 ❌	0 🔥	1m 51s ⏱️

[github-actions]

Automated Code Review

Reviewers: 4 | Confidence: 89% | Result: All clear

Reviewed: Correctness, Security Reliability, Test Coverage, Design Approach

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Automated review by peibekwe's agents

[Copilot]

Pull request overview

Adds Python declarative-workflow support for InvokeMcpTool, bringing the Python SDK closer to the existing .NET MCP action support and exposing the feature through the declarative workflow factory, executor, handler, tests, and samples.

Changes:

• Adds the Python InvokeMcpTool executor/handler path, including approval-flow support and WorkflowFactory(mcp_tool_handler=...).
• Exposes the new MCP workflow types through declarative package exports and core re-exports.
• Adds unit tests plus a new declarative sample demonstrating MCP-backed document search with a downstream agent.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
python/samples/03-workflows/declarative/invoke_mcp_tool/workflow.yaml	New sample workflow invoking an MCP tool, storing results, and passing context to an agent.
python/samples/03-workflows/declarative/invoke_mcp_tool/main.py	Sample runner for the MCP workflow, including optional approval prompts.
python/packages/declarative/tests/test_invoke_mcp_tool_executor.py	New executor-focused tests for validation, output handling, approval flow, and errors.
python/packages/declarative/tests/test_default_mcp_tool_handler.py	New handler-focused tests for caching, lifecycle, normalization, and error mapping.
python/packages/declarative/AGENTS.md	Documents the new MCP transport abstractions in the declarative package overview.
python/packages/declarative/agent_framework_declarative/_workflows/_mcp_handler.py	Implements the MCP handler protocol and default streamable-HTTP-backed handler.
python/packages/declarative/agent_framework_declarative/_workflows/_factory.py	Threads mcp_tool_handler through WorkflowFactory.
python/packages/declarative/agent_framework_declarative/_workflows/_executors_mcp.py	Adds the InvokeMcpTool executor, result parsing, approval flow, and conversation integration.
python/packages/declarative/agent_framework_declarative/_workflows/_declarative_builder.py	Registers InvokeMcpTool, validates required fields, and enforces handler presence.
python/packages/declarative/agent_framework_declarative/_workflows/__init__.py	Re-exports MCP executor and handler symbols from the workflows package.
python/packages/declarative/agent_framework_declarative/__init__.py	Re-exports MCP workflow symbols from the declarative package root.
python/packages/core/agent_framework/declarative/__init__.pyi	Updates type stubs for the new declarative MCP exports.
python/packages/core/agent_framework/declarative/__init__.py	Updates lazy core re-exports to surface the new declarative MCP types.

[github-actions]

Automated Code Review

Reviewers: 3 | Confidence: 83% | Result: All clear

Reviewed: Correctness, Security Reliability, Design Approach

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Automated review by peibekwe's agents