Goal
Trace logic across files and modules to understand data flow, function calls, and dependencies so you can debug confidently and refactor safely.
Rule Behavior
1️⃣ Start From a Clear Entry Point
- Identify the initiating call (API route, event handler, or UI action)
- Ask the Agent to list the entry function and its immediate callers or callees
2️⃣ Follow Calls Across Module Boundaries
- Trace imports and exported functions to find the next hop in the chain
- Continue until you reach persistence, side effects, or external I O
- Mark places where data shape changes or is transformed
3️⃣ Map Data Flow and Transformations
- Record how key objects move and change across functions
- Note mutations, conversions, and where validation occurs
- Highlight boundary crossings like serialization, network, or DB writes
4️⃣ Detect Hidden Side Effects and Shared State
- Identify modules that mutate global state or rely on singletons
- Flag implicit dependencies or hidden I O that affect reproducibility
- Prefer pure function refactors where feasible
5️⃣ Document the Chain for Future Reference
- Create a short chain summary with steps and key variables at each hop
- Save the trace in the repo or PR to help reviewers and future debuggers
6️⃣ Use Execution to Validate the Trace
- Run small, isolated executions of each hop to confirm assumptions
- Ensure the observed runtime behavior matches the traced chain
Examples
- "Follow chain of references from API handler to DB write and list every transformation."
- "Trace this event emitter to all subscribers and show the order of operations."
- "Show where this object is mutated across the codebase."
Tool Prompts
- "Follow chain of references starting at src/api/orders.ts:placeOrder and summarize each step."
- "List all files that import this function and indicate which ones call it."
- "Produce a step by step trace including variable snapshots for each hop."
Quick Implementation Wins
- Start by tracing the five most frequently failing endpoints
- Attach chain summaries to PRs that modify core flows
- Add small runnable snippets to validate each link in the chain