codebase-memory

# Codebase Memory — Knowledge Graph Tools Graph tools return precise structural results in ~500 tokens vs ~80K for grep. ## Quick Decision Matrix | Question | Tool call | |----------|----------| | Who calls X? | `trace_path(direction="inbound")` | | What does X call? | `trace_path(direction="outbound")` | | Full call context | `trace_path(direction="both")` | | Find by name pattern | `search_graph(name_pattern="...")` | | Dead code | `search_graph(max_degree=0, exclude_entry_points=true)` | | Cross-service edges | `query_graph` with Cypher | | Impact of local changes | `detect_changes()` | | Risk-classified trace | `trace_path(risk_labels=true)` | | Text search | `search_code` or Grep | ## Exploration Workflow 1. `list_projects` — check if project is indexed 2. `get_graph_schema` — understand node/edge types 3. `search_graph(label="Function", name_pattern=".*Pattern.*")` — find code 4. `get_code_snippet(qualified_name="project.path.FuncName")` — read source ## Tracing Workflow 1. `search_graph(name_pattern=".*FuncName.*")` — discover exact name 2. `trace_path(function_name="FuncName", direction="both", depth=3)` — trace 3. `detect_changes()` — map git diff to affected symbols ## Quality Analysis - Dead code: `search_graph(max_degree=0, exclude_entry_points=true)` - High fan-out: `search_graph(min_degree=10, relationship="CALLS", direction="outbound")` - High fan-in: `search_graph(min_degree=10, relationship="CALLS", direction="inbound")` ## 14 MCP Tools `index_repository`, `index_status`, `list_projects`, `delete_project`, `search_graph`, `search_code`, `trace_path`, `detect_changes`, `query_graph`, `get_graph_schema`, `get_code_snippet`, `get_architecture`, `manage_adr`, `ingest_traces` ## Edge Types CALLS, HTTP_CALLS, ASYNC_CALLS, IMPORTS, DEFINES, DEFINES_METHOD, HANDLES, IMPLEMENTS, OVERRIDE, USAGE, FILE_CHANGES_WITH, CONTAINS_FILE, CONTAINS_FOLDER, CONTAINS_PACKAGE ## Cypher Examples (for query_graph) ``` MATCH (a)-[r:HTTP_CALLS]->(b) RETURN a.name, b.name, r.url_path, r.confidence LIMIT 20 MATCH (f:Function) WHERE f.name =~ '.*Handler.*' RETURN f.name, f.file_path MATCH (a)-[r:CALLS]->(b) WHERE a.name = 'main' RETURN b.name ``` ## Gotchas 1. `search_graph(relationship="HTTP_CALLS")` filters nodes by degree — use `query_graph` with Cypher to see actual edges. 2. `query_graph` has a 200-row cap — use `search_graph` with degree filters for counting. 3. `trace_path` needs exact names — use `search_graph(name_pattern=...)` first. 4. `direction="outbound"` misses cross-service callers — use `direction="both"`. 5. Results default to 10 per page — check `has_more` and use `offset`.