| name | trace-mcp |
| description | Use trace-mcp tools for code navigation, impact analysis, and framework-aware queries instead of Read/Grep/Glob/Bash. Activate whenever the agent needs to explore, understand, or modify a codebase that has trace-mcp indexed. |
trace-mcp — Code Intelligence Routing
trace-mcp is a framework-aware code intelligence MCP server. It exposes 120+ tools that return semantic, structured results over a cross-language dependency graph. When trace-mcp is available, it is almost always cheaper and more accurate than native file tools.
When to Use
Activate this skill whenever you need to:
- Find a function, class, method, route, component, or any symbol
- Understand a file, module, or feature before editing
- Determine what breaks if you change something
- Trace a request flow, call graph, or data flow
- Audit architecture, dead code, tests, or security
Do not use Read, Grep, Glob, or shell ls/find/cat/head/tail for exploring source code (.ts, .js, .py, .php, .go, .rb, .java, etc.). Use trace-mcp tools instead. Native tools stay allowed only for non-code files (.md, .json, .yaml, configs) or immediately before an Edit on a known file.
Start-of-Session Checklist
get_project_map with summary_only=true — orient yourself to the project structure
get_task_context with task: "<natural-language description>" — gather all relevant code in a single call instead of chaining search → get_symbol → Read
Decision Matrix
| Task | trace-mcp tool | Instead of |
|---|
| Find a symbol by name | search | Grep |
| Understand a file before editing | get_outline | Read (full file) |
| Read one symbol's source | get_symbol | Read (full file) |
| Multiple symbols + shared imports | get_context_bundle | chained get_symbol |
| What breaks if I change X | get_change_impact | guessing |
| Who calls this / what does it call | get_call_graph | Grep |
| All usages of a symbol | find_usages | Grep |
| Implementations of an interface | get_type_hierarchy | Grep / ls |
| Classes implementing X | search with implements filter | Grep |
| Tests for a symbol or file | get_tests_for | Glob + Grep |
| Project overview | get_project_map (summary_only) | Bash ls/find |
| Context for a task | get_task_context / get_feature_context | reading many files |
| HTTP request flow | get_request_flow | reading route + controller files |
| DB model relationships | get_model_context | reading model + migrations |
| Component tree | get_component_tree | reading component files |
| Circular dependencies | get_circular_imports | manual tracing |
| Dead code / dead exports | get_dead_code / get_dead_exports | Grep for unused |
| Project health / coverage gaps | self_audit | manual inspection |
| Complexity / hotspots | get_complexity_report / get_risk_hotspots | guessing |
Token-Efficiency Rules
- Batch independent queries. Use
batch when you need 2+ independent tool calls:
batch({ calls: [
{ tool: "get_outline", args: { path: "src/foo.ts" } },
{ tool: "get_outline", args: { path: "src/bar.ts" } },
{ tool: "search", args: { query: "handleRequest", kind: "function" } }
]})
- Never read the same file twice. Use
get_outline once, then get_symbol for specific pieces.
- Prefer
get_context_bundle over chained get_symbol calls — it deduplicates shared imports.
- Read-before-Edit optimization. When you must
Read a file to edit it:
- Call
get_outline first to find the line range of the target symbol.
- Read only that range with
offset + limit. Never read a 500-line file to edit 5 lines.
- Do not delegate code exploration to subagents. Agent subprocesses carry ~50k tokens of overhead before doing anything. Use trace-mcp tools in the main conversation instead.
After Editing a File
- Call
register_edit with the edited file_path to reindex just that file and invalidate caches. This is much lighter than a full reindex and keeps subsequent queries accurate.
- If the response includes
_duplication_warnings, review the referenced symbols — you may be duplicating existing logic.
- Do not re-read the file to "verify" the edit. The
Edit tool already confirmed success.
Before Creating New Symbols
- Call
check_duplication with { name, kind } to verify no similar symbol exists. Prevents reinventing existing logic.
Health Checks (Once Per Session)
audit_config — stale references in CLAUDE.md / settings
self_audit — dead exports, untested code, hotspots
get_tech_debt — per-module tech-debt grades
get_optimization_report — detects repeated reads, Bash grep usage, missed trace-mcp opportunities
Related Skills
trace-mcp-refactoring — safe refactoring workflow (risk assessment → rename → impact check)
trace-mcp-codemod — bulk mechanical changes via apply_codemod
trace-mcp-pre-commit — security, quality-gate, and antipattern checks before commit