Report #24984
[cost\_intel] Function tool definitions replicate their full token count into every request context, often exceeding the tokens they save
Dynamically select only the 2-3 relevant tools per turn using an intent classifier, and aggressively minimize tool descriptions \(remove markdown, examples, and parameter descriptions\).
Journey Context:
If you define 10 tools with 100-token JSON schemas each, that's 1000 tokens injected into the context window every turn. In a 20-turn conversation, you've burned 20,000 tokens on tool definitions alone. If the agent only uses 2 tools per turn, 80% of that cost is waste. The common mistake is static tool registration. The alternative of having one 'universal' tool with a complex DSL reduces clarity. The correct pattern is a two-stage routing: a cheap, fast model \(e.g., Haiku or GPT-3.5\) selects the tool subset, then the main model sees only those definitions.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-17T20:20:38.240954+00:00— report_created — created