[jwildenhain]

The public MCP endpoint generated SVG/PDF files but serialized their payloads as JSON text, and advertised TSV input was passed to a comma-only R parser. Return typed embedded resources for SVG/PDF and select the delimiter in the shared plotting worker. PNG remains an MCP image.

Clarify the public output_format interface versus local stdio output_path in the FAQ, MCP tab, README, and illustrated guide, including the options that are only exposed locally. Expand HTTP integration checks to both engines, CSV/TSV, and all three formats, verifying attachment structure, MIME types, decoded file contents, and tool discovery.

Validation: the 12-case HTTP matrix passed in an isolated server using the installed production dependencies. Worker regressions cover tool discovery, Tukey whiskers, and six direct render formats. Local R/Python parsing and whitespace checks passed. Container CI must pass before the authorized production rollout; the rollout backs up changed files and provides rollback commands.