{"record":{"id":"268adfd5bf7a92fe","repo":"pbakaus/impeccable","slug":"concept-seed-grain-must-be-one-of-composition","errorCode":null,"errorMessage":"concept-seed: --grain must be one of ${COMPOSITION_GRAINS.join(', ')}","messagePattern":"concept-seed: --grain must be one of (.+?)","errorType":"validation","errorClass":null,"httpStatus":null,"severity":"error","filePath":"plugin/skills/impeccable/scripts/concept-seed.mjs","lineNumber":327,"sourceCode":"  if (!Number.isInteger(reroll) || reroll < 0) {\n    throw new Error('concept-seed: --reroll must be a non-negative integer');\n  }\n  if (register !== null && register !== 'safer' && register !== 'bolder') {\n    throw new Error('concept-seed: --register must be safer or bolder');\n  }\n  if (register !== null && reroll < 1) {\n    throw new Error('concept-seed: --register steers a re-roll round; pass --reroll <n> with it');\n  }\n  if (register !== null && scope !== 'direction') {\n    throw new Error('concept-seed: --register applies to direction rounds only');\n  }\n  if (mode !== null && !SEED_MODES.has(mode)) {\n    throw new Error('concept-seed: --mode must be persuade, operate, read, or experience');\n  }\n  // Grain needs no mode: how much of the product is in play is independent of\n  // which register of work it is.\n  if (grain !== null && !COMPOSITION_GRAINS.includes(grain)) {\n    throw new Error(`concept-seed: --grain must be one of ${COMPOSITION_GRAINS.join(', ')}`);\n  }\n  if (platform !== null && !COMPOSITION_PLATFORMS.includes(platform)) {\n    throw new Error(`concept-seed: --platform must be one of ${COMPOSITION_PLATFORMS.join(', ')}`);\n  }\n  if (!Number.isInteger(candidateCount) || candidateCount < 5 || candidateCount > 7) {\n    throw new Error('concept-seed: --candidate-count must be an integer from 5 to 7');\n  }\n  const unit = (salt) => {\n    const h = crypto.createHash('sha256').update(`${scope}:${salt}:${key}`).digest();\n    return h.readUInt32BE(0) / 0xffffffff;\n  };\n  const indexSalt = reroll === 0 ? 'index' : `index:reroll-${reroll}`;\n  const buildIndex = 3 + Math.floor(unit(indexSalt) * (candidateCount - 2)); // 3..candidateCount\n  // Surface scope deals a hand of three grounded structures: one card is not\n  // a choice, and the full ranked list would hand selection back to the\n  // model's taste. The dice pick all three; the primary index leads. The\n  // no-lineup rule stays direction-only, where it was written for worlds.\n  const dealtIndices = [buildIndex];","sourceCodeStart":309,"sourceCodeEnd":345,"githubUrl":"https://github.com/pbakaus/impeccable/blob/d14711ae3d1a1dd62dee61a358d27f107c51ccd0/plugin/skills/impeccable/scripts/concept-seed.mjs#L309-L345","documentation":"Thrown when --grain is provided but is not one of COMPOSITION_GRAINS: product, flow, view, region. Grain names how much of the product is in play (a whole site vs. a flow vs. one view vs. a region), and only those four values are cataloged. null/undefined means no grain preference and is allowed.","triggerScenarios":"Passing --grain with a value like 'page', 'section', 'component', 'app', 'screen' — none are valid. The check is grain !== null && !COMPOSITION_GRAINS.includes(grain).","commonSituations":"CLI typo; using a near-synonym ('section' instead of 'region', 'page' instead of 'view'); a UI exposing free-text grain.","solutions":["Use exactly one of: --grain product, --grain flow, --grain view, --grain region.","Omit --grain to deal compositions without a grain preference."],"exampleFix":"# before\n$ node concept-seed.mjs --scope surface --grain section ...\n\n# after\n$ node concept-seed.mjs --scope surface --grain region ...","handlingStrategy":"validation","validationCode":"const COMPOSITION_GRAINS = ['product', 'flow', 'view', 'region'];\nif (grain != null && !COMPOSITION_GRAINS.includes(grain)) {\n  throw new Error(`--grain must be one of: ${COMPOSITION_GRAINS.join(', ')}`);\n}","typeGuard":"function isValidGrain(value) {\n  return value == null || ['product','flow','view','region'].includes(value);\n}","tryCatchPattern":"try {\n  await seedConcepts({ scope, grain });\n} catch (err) {\n  if (/--grain must be one of/.test(err.message)) {\n    console.error('Use --grain product|flow|view|region, or omit it.');\n  } else throw err;\n}","preventionTips":["Parse --grain as an enum; reject near-synonyms (section/page) at the CLI.","Share the COMPOSITION_GRAINS constant between CLI, seeder, and catalog validator.","Document that grain is optional and means 'no preference' when omitted."],"tags":["concept-seed","validation","grain","cli-args"],"backgroundTag":null,"analyzedSha":"d14711ae3d1a1dd62dee61a358d27f107c51ccd0","analyzedAt":"2026-08-13T00:52:25.771Z","schemaVersion":2},"datasetVersion":"2026-08-13T04:17:16.726Z"}