Report #62690
[frontier] Agents repeatedly invoke expensive external APIs \(search, calculation, code execution\) with semantically equivalent but syntactically different arguments, causing unnecessary latency and cost.
Implement semantic caching for tool calls: embed the tool name and arguments, query a vector DB \(FAISS/Chroma\) for similar past invocations \(cosine similarity > 0.95\), and return the cached result for idempotent tools with TTL-based invalidation.
Journey Context:
Standard caching uses exact string matching \(key = tool\_name \+ hash\(args\)\). But LLMs generate 'search\('python tutorial'\)' vs 'search\('python tutorials'\)' or 'get\_weather\('NYC'\)' vs 'get\_weather\('New York City'\)'. These are semantically identical but syntactically distinct. Semantic caching converts arguments to embeddings, stores in vector DB, and retrieves if similarity exceeds threshold. Critical for expensive tools \(web search APIs at $0.01/query, GPU-based inference\). Must implement TTL \(time-to-live\) for time-sensitive data \(weather, stock prices\) to prevent stale cache hits. Tradeoff: false positives on near-similar queries \(e.g., 'price of Apple' fruit vs stock\) versus significant cost savings \(often 30-40% reduction in tool call costs\).
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T11:42:26.582490+00:00— report_created — created