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New results show that wiring coding agents to traverse a code dependency graph outperforms expanding context or keyword/vector retrieval on architecture-heavy tasks where critical files are semantically distant.

An arXiv study introduces the Navigation Paradox: as context windows grow, failures shift from retrieval capacity to navigational salience, and presents CodeCompass, an MCP-based graph tool exposing IMPORTS/INHERITS/INSTANTIATES edges during agent runs with Claude Code; on a FastAPI RealWorld benchmark, BM25 hits 100% on semantic (G1) tasks but gives no lift on hidden-dependency (G3) tasks (78.2% vs 76.2% baseline), while CodeCompass reaches 99.4% ACS on G3, a +23.2 point jump over both baselines (paper, code/benchmark).
Crucially, benefit depends on tool invocation: trials that actually used the graph (42%) averaged 99.5% ACS; those that skipped it despite instructions scored 80.2%, indistinguishable from vanilla—highlighting that prompt design and agent policies must reliably trigger graph consultation.
For teams piloting repo-level agents, treat structural navigation as a first-class capability: generate a per-repo AST-derived dependency graph, expose it via MCP, and enforce early graph lookups when touching modules with broad non-local impact; the author also shares a practitioner-friendly narrative on why assistants miss critical files Medium.