Browser Tool Action Inventory

Give browsing agents a small closed command set — search, click-by-ID, find, quote, scroll, back, end — instead of free-form browser scripting.

WebGPT’s ACI exposes a fixed command vocabulary: Search, Clicked on link <link ID>, Find in page, Quote, scroll up/down by N, Top, Back, and End: Answer / End: Nonsense|Controversial. Observations use lm-oriented web observations with stable link IDs so click targets are parseable. Prefer a modern search API so the LM practices using a search engine, not reimplementing retrieval indices (retrieval-augmented generation remains the alternative when you own the corpus).

Keep the inventory small under ACI design principles and tool inventory. Treat non-matching generations as invalid actions that still spend budget. Episode shape often splits into browse-then-answer phases.

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Sources

• WebGPT (Nakano et al.), §2 Table 1