[Refactor] Add a small factory for MCP test clients

[Robbo-lab]

Issue Type

• Bug report
• Feature request
• Documentation update
• Other (please specify)

Other: factory / test-infrastructure improvement

Description

The MCP test setup already has reusable client code, but the request setup is still fairly manual. A small factory would make test setup cleaner and easier to extend. This is a good fit for v0.0.1 because it improves infrastructure now and helps later work in v0.0.2.

Steps to Reproduce (for bugs)

1. Open tests/mcp/conftest.py
2. Review how the MCP test client and request defaults are set up
3. Note that common setup values are still handled fairly manually
4. Observe that a small factory would make reuse and extension easier

Expected behaviour

Test infrastructure should have one small factory/helper for creating MCP test clients with shared defaults.

Actual behaviour

The current setup works, but common test-client setup details are more manual than they need to be.

Screenshots

Not applicable.

Additional context

Proposed scope:

• Add a small factory/helper for creating MCP test clients
• Include the common request defaults in one place
• Keep it focused on test infrastructure only
• Do not change production code behavior

Out of scope:

• A full dependency injection system
• Refactoring the whole test suite at once
• Changing MCP protocol behavior
• Production client factories

Acceptance criteria:

• A small MCP test client factory exists in test infrastructure
• Common setup values are defined in one place
• Tests can use the factory instead of repeating setup details
• Production behavior stays unchanged

Possible Solution

Add one small helper like build_mcp_test_client() that creates the client with default headers, protocol version, and initialization values. Start by using it in one or two tests first.

Your Environment (for bugs):

• Operating System: N/A
• Browser (if applicable): N/A
• Version of the software: current main branch

[leventfhxy-sudo]

Hi，i would like do this. Is it still available？

[Robbo-lab]

Hi，i would like do this. Is it still available？

Hi @leventfhxy-sudo can you provide some detail on how you would do this as we are looking to make sure that we have the ability to switch clients

[leventfhxy-sudo]

The core idea is that we introduce a frozen dataclass called MCPRequestDefaults that acts as a complete client profile — it holds every configurable value (client name, protocol version, capabilities, accept header, etc.) in one immutable object. Switching clients then becomes as simple as swapping which MCPRequestDefaults instance you pass into the build_mcp_test_client() factory function. For small tweaks you use dataclasses.replace() to derive a new profile from an existing one with just the fields you want to change, like replace(MCPRequestDefaults(), client_name="pytest-stream", accept="text/event-stream, application/json"). For recurring profiles that multiple tests share, you define named constants like STREAMING_CLIENT or LEGACY_CLIENT at module level and reference them wherever needed. And if you want to run the same test logic against multiple client configurations, you can use @pytest.mark.parametrize with a list of these defaults objects so pytest automatically runs the test once per profile. The factory itself is stateless — it just reads whatever defaults you give it, optionally runs the initialization handshake, and returns a ready-to-use MCPTestClient that also stores a reference to its own defaults via self.defaults so tests can introspect the configuration at any point. This means adding a new client variant in the future requires zero changes to the factory or the client class — you just create a new MCPRequestDefaults(...) with the values you need and pass it in.

[Robbo-lab]

@leventfhxy-sudo Thanks you for this we have work going on in another PR #37 to change the nature of the LLM interface and abstraction, wait for this work to merged please and review and perhaps update uour approach or even suggest a change to the issue scope.