Semantic Delta Streaming: shipping only what changed on the page — Weavetab Research

Full DOM snapshots waste tokens and latency. We describe the delta protocol Weavetab MCP uses to stream only meaningful semantic changes to a language model, cutting per-turn payloads by 78% on average across 12,000 browsing sessions.

Semantic Delta Streaming: shipping only what changed on the page

Published: 2026-07-08

Full DOM snapshots waste tokens and latency. We describe the delta protocol Weavetab MCP uses to stream only meaningful semantic changes to a language model, cutting per-turn payloads by 78% on average across 12,000 browsing sessions.

## Motivation

Most browser-automation stacks ship a fresh accessibility tree — or worse, raw HTML — on every model turn. For long-running agents this is prohibitively expensive: the median page in our corpus produces 41 KB of tree data, and 92% of it is unchanged between consecutive turns.

## Method

We define a **semantic delta** as the minimal set of node-level operations required to transform the last snapshot the model observed into the current one. The delta operates over an accessibility-derived tree, not the DOM, so purely stylistic mutations are collapsed.

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