trace_path returns empty for all functions despite traversable CALLS edges (v0.8.1, macOS arm64)

[mattiagggg]

Summary

trace_path returns an empty result for every function/method I tried — callers or callees, plain or fully-qualified name, any depth — even though the underlying CALLS edges exist and are traversable via query_graph. The tool only ever echoes back {"function":...,"direction":...} with no paths/nodes.

This makes the headline call-graph traversal tool effectively non-functional in v0.8.1, at least on macOS arm64.

Environment

• Version: codebase-memory-mcp 0.8.1
• Platform: Darwin arm64 (macOS)
• Repo indexed: large polyglot repo (Python 569 files, Go 190, TS 20, …) → 15,915 nodes / 67,668 edges, status:"indexed". Index reports 15,945 CALLS edges.

Repro

Index any multi-language repo, then:

$ codebase-memory-mcp cli trace_path '{"project":"<proj>","function_name":"read_file_status","direction":"callers","depth":1}'
{"function":"read_file_status","direction":"callers"}

Empty — no paths. But the edges clearly exist:

$ codebase-memory-mcp cli query_graph '{"project":"<proj>","query":"MATCH (a)-[:CALLS]->(b:Function) RETURN b.name, count(a) AS callers ORDER BY callers DESC LIMIT 8"}'
{"columns":["b.name","callers"],"rows":[["get",380],["info",374],["main",169],["load",112],["read_file_status",88],["save_files_from_dict",87],["WithTimeout",72],["keys",63]]}

read_file_status is a Function node with 88 incoming CALLS edges, yet trace_path finds nothing.

What I ruled out

• Not a label issue. Tried both Method nodes (create) and Function nodes (read_file_status, save_files_from_dict, main, run_cmd) — all empty.
• Not direction. callers and callees both empty.
• Not name resolution. Bare name and fully-qualified (agentsv2.base_agent.BaseAgent.create) both empty.
• Not missing data. The exact CALLS edges traverse fine via query_graph, so the graph is populated correctly — only the trace_path start-node lookup (or its traversal) appears to fail.

Expected

trace_path should return the caller/callee paths for read_file_status (88 callers exist), matching what query_graph can already walk.

Workaround

Use query_graph with a Cypher MATCH ... -[:CALLS*]-> ... instead; the graph data itself is correct.

[halindrome]

Confirming this is a real bug — reproduced independently on a separate repo and on a build from current main (not just v0.8.1), also macOS arm64.

A Perl project indexed with the same tree shows three refreshProperties definitions each with inbound CALLS edges via query_graph:

query_graph  MATCH (a)-[:CALLS]->(b:Function) WHERE b.name='refreshProperties' ...
→ Corvex.Assets.refreshProperties    8 callers
  Corvex.Objects.refreshProperties   6 callers
  Corvex.Questions.refreshProperties 5 callers

…but trace_path returns empty for the same functions, with both the bare and fully-qualified name:

trace_path {"function_name":"refreshProperties","direction":"callers","depth":1}
→ {"function":"refreshProperties","direction":"callers"}

trace_path {"function_name":"<proj>.apps.rest-api.lib.Corvex.Assets.refreshProperties","direction":"callers","depth":1}
→ {"function":"<proj>...refreshProperties","direction":"callers"}

So the response carries no paths/nodes key at all — matching the report. The graph data is correct and walkable via Cypher (MATCH ... -[:CALLS]-> ...), so this is isolated to trace_path's own start-node lookup/traversal, not edge creation or name resolution. The query_graph Cypher workaround in the issue holds up.