Trimming the Minimal usage block out of elements.md (65c31832) lost
arg-shape templates that the A/B harness depends on. Text-only LLMs
in the treatment arm see only the markdown skill content — no MCP
tools/list, no published inputSchema — so without the per-tool
example payloads they have to guess argument names and break M1.
Restore the full block as a sibling skill `elements-cookbook` (same
hasMcpTools flag, slightly later priority so it loads alongside
elements). Wire it through buildFullPrompt + the
get_design_prompt(section='elements-cookbook') section map. Update
the A/B harness to also strip the cookbook body when building the
baseline prompt — leaving it in B would leak tool names + arg shapes
back into the no-tools variant and re-bias the comparison.
Both files now under the 800-line per-file ceiling.
f5eff2c9a3