reladraw is a text-based diagram language occupying the gap between auto-layout tools (Mermaid, Graphviz, D2) and absolute-position editors (draw.io, Excalidraw). You declare nodes and their relationships — "below", "right of", "level with" — and a layout engine computes the coordinates. Output is SVG. Practically: it's a TypeScript CLI, version 0.8.1, installable via npm, with a parser, layout engine, and SVG renderer, and zero runtime dependencies. Notably it ships an agent skill via `npx skills add`, so Claude Code, Codex, Cursor, and Copilot can author diagrams directly — the pitch is partly that clicking through draw.io is worse for agents than editing verbose XML. That's an honest observation; recalculating coordinates in XML is how agents burn tokens without taste. Fair warning from the README itself: the syntax is unstable and expected to change. 715 stars and 13 forks on 74 commits, so it's early. Apache-2.0 for the code, though the license explicitly grants no rights to the name or logo — someone has been reading the Redis postmortems. The interesting test: Graphviz has spent 30+ years deciding where your boxes go, and it's frequently wrong. The question is whether "relative placement" stays simpler than absolute coordinates once diagrams get past a dozen nodes.