Add script debugger MCP tools, CLI REPL, and RPC mode#395
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Add script debugger MCP tools, CLI REPL, and RPC mode#395
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- Add 13 MCP debug tools (debug_start_session, debug_set_breakpoints, debug_wait_for_stop, debug_get_stack, debug_get_variables, debug_evaluate, debug_continue, debug_step_over/into/out, debug_end_session, debug_list_sessions, debug_capture_at_breakpoint) to CARTRIDGES, SCAPI, and STOREFRONTNEXT toolsets - Add ServerContext for persistent server-scoped state across MCP tool invocations (debug sessions, future log watches) - Add DebugSessionRegistry with TTL cleanup and multi-session support - Add `b2c debug cli` command with interactive REPL and --rpc mode for JSONL-over-stdio headless/agent integration - Add resolveBreakpointPath utility in SDK for flexible path normalization (server paths, local paths, cartridge-prefixed paths) - Add debug command docs and b2c-debug agent skill
Group debug tools on a single Diagnostics page instead of individual pages. Add Diagnostics sub-heading under MCP Tools in the sidebar for future tools like log tailing.
Organize into Cartridges, SCAPI, PWA Kit, Storefront Next, and Diagnostics sub-groups.
Make it explicit in tool descriptions and docs that these tools block until a breakpoint is hit or timeout expires, and that the caller must trigger a request externally while waiting.
1. capture_at_breakpoint: add trigger_url parameter so the tool can fire the HTTP request itself after arming the breakpoint, avoiding the blocking coordination problem with LLM tool-calling. 2. set_breakpoints: surface warnings when a path cannot be round-trip mapped back to a local file. Set verified=false for unmapped paths instead of silently accepting them. 3. Tool descriptions: steer toward the non-blocking workflow (set_breakpoints → trigger → list_sessions → inspect) rather than leading with blocking tools. 4. list_sessions: include active breakpoints with resolved server paths so agents can inspect what's armed on the server. 5. start_session: return cartridge_mappings (name → local path) so agents can verify cartridge discovery and path mapping.
Absolute local paths like /Users/.../app_mysite/cartridge/controllers/Loyalty.js start with / and were returned as-is (treated as server paths) before the source mapper had a chance to map them. Now the source mapper runs first — if it matches, the local path is correctly converted to a server path. The / passthrough only applies if the mapper doesn't match.
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Summary
b2c debug cli— interactive REPL for terminal-based debugging with--rpcflag for JSONL-over-stdio headless/agent integrationresolveBreakpointPath— SDK utility that normalizes file paths for breakpoints (server paths, local paths, cartridge-name-prefixed paths)Test plan
test-rpc-debug.shend-to-end via JSONL stdin/stdoutpnpm run test:agent)pnpm -w run docs:build)