POST /api/v1/md and POST /api/v1/markdown used to count every character of your markdown, including data: image payloads. Inlining a single 150KB PNG as base64 is roughly 200KB of text, so one local image could consume the entire input budget.
The 200KB cap now measures the text only: each inline data: image URL is excluded from the count. Inline images are bounded by the same rules as remote images — 5MB decoded per image and 20 images per document — and the whole request body is capped at 15MB.
Nothing changes for text-only documents, and remote images are untouched. The /md/validate pre-flight, the MCP render_markdown and validate_markdown tools, the web editor and the lint page all apply the same split, as does the anonymous /md path (still capped at 20 pages and the same per-IP rate limits).