🧪TDD Challenge·advanced·⏱️ 40–55m·⭐ 250 XP
M-052Build an MCP Tool Composition Pipeline
Description
Nebula Corp's AI assistants need to chain multiple MCP tools together to answer complex queries. Build a tool composition engine that takes a plan (a sequence of tool calls where later steps can reference earlier results), executes them in order, and returns the combined result. Handle errors gracefully — if one step fails, the pipeline should report which step failed and why.
Test Cases (3)
Simple single-step pipeline
Single step should execute and return result
Input:executePipeline([{ id: 'step1', tool: 'lookup_customer', args: { customerId: 'C001' } }])
Expected:CONTAINS:Alice
Multi-step with references
Step 2 should use step 1's result
Input:executePipeline([{ id: 'step1', tool: 'lookup_customer', args: { customerId: 'C001' } }, { id: 'step2', tool: 'get_plan_price', args: { plan: '$step1.data.plan' } }])
Expected:CONTAINS:49
Pipeline failure stops execution
Should stop at first failure and report which step failed
Input:executePipeline([{ id: 'step1', tool: 'lookup_customer', args: { customerId: 'C999' } }, { id: 'step2', tool: 'get_plan_price', args: { plan: '$step1.data.plan' } }])
Expected:CONTAINS:failed
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